[DOC] Fix deprecation warning, deprecations and type hints

[hectormz]

PR Description

Please describe the changes proposed in the pull request:

• Fix f-string for argument deprecation warning (!!)
• Updated deprecated arguments in tests
• Add type hints to some function returns

This PR resolves #59 .

PR Checklist

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1. PR in from a fork off your branch. Do not PR from <your_username>:master, but rather from <your_username>:<branch_name>.

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Code Changes

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• Ensure that you have added tests.
• Run all tests ($ pytest .) locally on your machine.
  • Check to ensure that test coverage covers the lines of code that you have added.
  • Ensure that all tests pass.

Relevant Reviewers

Please tag maintainers to review.

• @ericmjl

[codecov]

Codecov Report

Merging #383 into dev will increase coverage by 4.82%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##              dev     #383      +/-   ##
==========================================
+ Coverage   88.19%   93.01%   +4.82%     
==========================================
  Files          10       10              
  Lines         754      931     +177     
==========================================
+ Hits          665      866     +201     
+ Misses         89       65      -24

[ericmjl]

We're good here, merging. Thanks @HectorM14!

[hectormz]

Was there something I could/should have done to restart the pipelines?

[ericmjl]

That's under my control for the time being, while I hack on robustifying the Pipelines.