azure: case-insensitive UUID to avoid new IID during kernel upgrade (#798)

Kernel's newer than 4.15 present /sys/dmi/id/product_uuid as a
lowercase value. Previously UUID was uppercase.

Azure datasource reads the product_uuid directly as their platform's
instance-id. This presents a problem if a kernel is either
upgraded or downgraded across the 4.15 kernel version boundary because
the case of the UUID will change, resulting in cloud-init seeing a
"new" instance id and re-running all modules.

Re-running cc_ssh in cloud-init deletes and regenerates ssh_host keys
on a system which can cause concern on long-running instances that
somethingnefarious has happened.

Also add:
- An integration test for this for Azure Bionic Ubuntu FIPS upgrading from
   a FIPS kernel with uppercase UUID to a lowercase UUID in linux-azure
- A new pytest.mark.sru_next to collect all integration tests related to our
   next SRU

LP: #1835584

1 files changed, 4 insertions, 2 deletions

diff --git a/tests/integration_tests/instances.py b/tests/integration_tests/instances.py
index 0d9852c3..055ec758 100644
--- a/tests/integration_tests/instances.py
+++ b/tests/integration_tests/instances.py
@@ -116,7 +116,8 @@ class IntegrationInstance:
     def install_new_cloud_init(
         self,
         source: CloudInitSource,
-        take_snapshot=True
+        take_snapshot=True,
+        clean=True,
     ):
         if source == CloudInitSource.DEB_PACKAGE:
             self.install_deb()
@@ -133,7 +134,8 @@ class IntegrationInstance:
             )
         version = self.execute('cloud-init -v').split()[-1]
         log.info('Installed cloud-init version: %s', version)
-        self.instance.clean()
+        if clean:
+            self.instance.clean()
         if take_snapshot:
             snapshot_id = self.snapshot()
             self.cloud.snapshot_id = snapshot_id