1948 Add Specifying Encoder Rule

[GibranHL0]

I have made things!

Closes #1948

Checklist

• [x] I have double checked that there are no unrelated changes in this pull request (old patches, accidental config files, etc)
• [x] I have created at least one test case for the changes I have made
• [x] I have updated the documentation for the changes I have made
• [x] I have added my changes to the CHANGELOG.md

Related issues

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[GibranHL0]

I used the following approach:

The open function has two ways to have the parameter encoding by the keyword encoding='utf-8' or being the fourth argument open('file.txt', 'r', -1, 'utf-8') . Then, I applied a visit_Call to check if the call is the function open and if it has the keyword encoding or a fourth parameter in the arguments.

[sobolevn]

For some reason our Actions do not start 🤔

[sobolevn]

Maybe we should recreate this PR? Actions might ignore it for some reason.

[GibranHL0]

Sure, I will open a new PR with the changes you made.

[GibranHL0]

I opened a new PR #2084 with the changes in the UnspecifiedEncodingViolation and the encoders to suppress warnings.

[sobolevn]

Thank you, I will close new one, let's keep more history here.

[GibranHL0]

Sure. Also, I committed a new change to the conf.py file because the encoder was not correct and it was causing warnings.

[Sxderp]

Encoding doesn't make sense when opened in binary mode. As the added tests don't have any binary mode tests I think this may be an oversight. What I'm not sure is if it should be OK to go without specifying encoding when in binary mode or if encoding=None is better. However, I don't know how difficult it is to make an exception for binary mode.