Add pytest warning filters for pkg_resource and sqlalchemy

[d33bs]

Description

This PR adds pytest warning filters for pkg_resource and sqlalchemy for convenience during testing (reducing the amount of default warning content displayed after running tests). I found there were still two pkg_resource warnings which occur after these changes, I believe due to the way certain CytoTable dependencies may reconfigure warning filters internally.

What is the nature of your change?

• Bug fix (fixes an issue).
• Enhancement (adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).
• This change requires a documentation update.

Checklist

Please ensure that all boxes are checked before indicating that a pull request is ready for review.

• I have read the CONTRIBUTING.md guidelines.
• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• New and existing unit tests pass locally with my changes.
• I have added tests that prove my fix is effective or that my feature works.
• I have deleted all non-relevant text in this pull request template.

[kenibrewer]

Good addition. Minor formatting suggestion at your discretion.

[d33bs]

Thank you @kenibrewer for your review and suggestion! Merging this in after applying changes.