Minor test updates

[vdplasthijs]

What does this PR do?

• Adding latest encoders and datasets to existing tests.
• Included a few more attributes to test for.
• Slightly changed the train/resume test (to be compatible with only saving the best epoch).

All tests (also slow) pass.

Before submitting

• Did you make sure title is self-explanatory and the description concisely explains the PR?
• Did you make sure your PR does only one thing, instead of bundling different changes together?
• Did you list all the breaking changes introduced by this pull request?
• Did you test your PR locally with pytest command?