Resolve datetime.datetime.utcnow() deprecation

[mdalp]

What was wrong?

Since python3.12 datetime.datetime.utcnow is deprecated, this raises a warning.

How was it fixed?

Using the .now() method passing the UTC timezone explicitly.
I used datetime.timezone.utc instead of datetime.UTC due to compatibility issues, i.e. py38 doesn't have the datetime.UTC shortcut to datetime.timezone.utc.

• CI before
• CI after

Todo:

• Clean up commit history
• Add or update documentation related to these changes
• Add entry to the release notes

Cute Animal Picture

[marcello-pv01]

CI failure is - likely - caused by flakiness depending on the performance of the CI node.
A restart should resolve it, but I don't think I can trigger a restart.

[kclowes]

LGTM! Thanks!