tox: bump the pinned flake8 and pylint version (#1029)

tox: bump the pinned flake8 and pylint version

* pylint: fix W1406 (redundant-u-string-prefix)

The u prefix for strings is no longer necessary in Python >=3.0.

* pylint: disable W1514 (unspecified-encoding)
    
From https://www.python.org/dev/peps/pep-0597/ (Python 3.10):
    
The new warning stems form https://www.python.org/dev/peps/pep-0597,
which says:
    
  Developers using macOS or Linux may forget that the default encoding
  is not always UTF-8. [...] Even Python experts may assume that the
  default encoding is UTF-8. This creates bugs that only happen on Windows.
    
The warning could be fixed by always specifying encoding='utf-8',
however we should be careful to not break environments which are not
utf-8 (or explicitly state that only utf-8 is supported). Let's silence
the warning for now.

* _quick_read_instance_id: cover the case where load_yaml() returns None

Spotted by pylint:
 - E1135 (unsupported-membership-test)
 - E1136 (unsubscriptable-object)

LP: #1944414

4 files changed, 16 insertions, 16 deletions

diff --git a/tests/unittests/test_datasource/test_azure.py b/tests/unittests/test_datasource/test_azure.py
index a4296bf6..d7206c72 100644
--- a/tests/unittests/test_datasource/test_azure.py
+++ b/tests/unittests/test_datasource/test_azure.py
@@ -912,13 +912,13 @@ scbus-1 on xpt0 bus 0
             'PreprovisionedVMType': None,
             'PreprovisionedVm': False,
             'datasource': {'Azure': {'agent_command': 'my_command'}},
-            'system_info': {'default_user': {'name': u'myuser'}}}
+            'system_info': {'default_user': {'name': 'myuser'}}}
         expected_metadata = {
             'azure_data': {
                 'configurationsettype': 'LinuxProvisioningConfiguration'},
             'imds': NETWORK_METADATA,
             'instance-id': EXAMPLE_UUID,
-            'local-hostname': u'myhost',
+            'local-hostname': 'myhost',
             'random_seed': 'wild'}
 
         crawled_metadata = dsrc.crawl_metadata()
@@ -1385,7 +1385,7 @@ scbus-1 on xpt0 bus 0
 
     def test_ovf_can_include_unicode(self):
         xml = construct_valid_ovf_env(data={})
-        xml = u'\ufeff{0}'.format(xml)
+        xml = '\ufeff{0}'.format(xml)
         dsrc = self._get_ds({'ovfcontent': xml})
         dsrc.get_data()
 
diff --git a/tests/unittests/test_datasource/test_configdrive.py b/tests/unittests/test_datasource/test_configdrive.py
index 2e2b7847..51097231 100644
--- a/tests/unittests/test_datasource/test_configdrive.py
+++ b/tests/unittests/test_datasource/test_configdrive.py
@@ -15,7 +15,7 @@ from cloudinit import util
 from cloudinit.tests.helpers import CiTestCase, ExitStack, mock, populate_dir
 
 
-PUBKEY = u'ssh-rsa AAAAB3NzaC1....sIkJhq8wdX+4I3A4cYbYP ubuntu@server-460\n'
+PUBKEY = 'ssh-rsa AAAAB3NzaC1....sIkJhq8wdX+4I3A4cYbYP ubuntu@server-460\n'
 EC2_META = {
     'ami-id': 'ami-00000001',
     'ami-launch-index': 0,
diff --git a/tests/unittests/test_datasource/test_openstack.py b/tests/unittests/test_datasource/test_openstack.py
index 478f3503..a9829c75 100644
--- a/tests/unittests/test_datasource/test_openstack.py
+++ b/tests/unittests/test_datasource/test_openstack.py
@@ -21,7 +21,7 @@ from cloudinit.sources.helpers import openstack
 from cloudinit import util
 
 BASE_URL = "http://169.254.169.254"
-PUBKEY = u'ssh-rsa AAAAB3NzaC1....sIkJhq8wdX+4I3A4cYbYP ubuntu@server-460\n'
+PUBKEY = 'ssh-rsa AAAAB3NzaC1....sIkJhq8wdX+4I3A4cYbYP ubuntu@server-460\n'
 EC2_META = {
     'ami-id': 'ami-00000001',
     'ami-launch-index': '0',
diff --git a/tests/unittests/test_datasource/test_scaleway.py b/tests/unittests/test_datasource/test_scaleway.py
index 32f3274a..f9e968c5 100644
--- a/tests/unittests/test_datasource/test_scaleway.py
+++ b/tests/unittests/test_datasource/test_scaleway.py
@@ -209,9 +209,9 @@ class TestDataSourceScaleway(HttprettyTestCase):
         self.assertEqual(self.datasource.get_instance_id(),
                          MetadataResponses.FAKE_METADATA['id'])
         self.assertEqual(self.datasource.get_public_ssh_keys().sort(), [
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA',
         ].sort())
         self.assertEqual(self.datasource.get_hostname(),
                          MetadataResponses.FAKE_METADATA['hostname'])
@@ -242,8 +242,8 @@ class TestDataSourceScaleway(HttprettyTestCase):
         ]
         self.datasource.metadata['ssh_public_keys'] = []
         self.assertEqual(self.datasource.get_public_ssh_keys().sort(), [
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
         ].sort())
 
     def test_ssh_keys_only_conf(self):
@@ -260,9 +260,9 @@ class TestDataSourceScaleway(HttprettyTestCase):
             'fingerprint': '2048 06:ff:...  login2 (RSA)'
         }]
         self.assertEqual(self.datasource.get_public_ssh_keys().sort(), [
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA',
         ].sort())
 
     def test_ssh_keys_both(self):
@@ -282,9 +282,9 @@ class TestDataSourceScaleway(HttprettyTestCase):
             'fingerprint': '2048 06:ff:...  login2 (RSA)'
         }]
         self.assertEqual(self.datasource.get_public_ssh_keys().sort(), [
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
-            u'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABCCCCC',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABDDDDD',
+            'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA',
         ].sort())
 
     @mock.patch('cloudinit.sources.DataSourceScaleway.EphemeralDHCPv4')