Python2 leftovers v2

[twizmwazin]

Your checklist for this pull request

• I've documented or updated the documentation of every API function and struct this PR changes.
• I've added tests that prove my fix is effective or that my feature works (if possible)

Detailed description

Rebases #2378 onto next, adds a commit updating shebangs to python3, I only found one.

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Test plan

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Closing issues

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[Rot127]

Please delete test_corpus.py. Shouldn't be used anywhere now.

[twizmwazin]

I also noticed that there are some files in suite that are unported. Do we need to port those?

[XVilka]

Most of the suite files probably should be removed as they are deprecated in favor of auto-sync tools.

[Rot127]

@kabeor @aquynh Please take a look.

[Rot127]

Most of the suite files probably should be removed as they are deprecated in favor of #2015 tools.

Yes, but let's do this before v6 (not here). Because they are not used. But this code here is run in the CI. Cleaning up suite is more than just the Pythin 2 files.

[Rot127]

@twizmwazin Any chance you find time to finish #2369 on behalf of @pyrox0? It is the only one for v5.0.2

[kabeor]

Thanks, merged!