feat: add Spotify authentication

[rocxteady]

New Pull Request Checklist

• I am not disclosing a vulnerability.
• I am creating this PR in reference to an issue.

Issue Description

This PR is for adding Spotify to 3rd party login providers.

Related issue: #55

Approach

TODOs before merging

• Add tests
• Add entry to changelog
• Add changes to documentation (guides, repository pages, in-code descriptions)

[parse-github-assistant]

Thanks for opening this pull request!

• 🎉 We are excited about your hands-on contribution!

[codecov]

Codecov Report

Merging #375 (db0b7e0) into main (b0bdf71) will increase coverage by 0.11%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #375      +/-   ##
==========================================
+ Coverage   89.54%   89.66%   +0.11%     
==========================================
  Files         152      155       +3     
  Lines       13969    14123     +154     
==========================================
+ Hits        12509    12663     +154     
  Misses       1460     1460              

Impacted Files	Coverage Δ
...on/3rd Party/ParseSpotify/ParseSpotify+async.swift	100.00% <100.00%> (ø)
.../3rd Party/ParseSpotify/ParseSpotify+combine.swift	100.00% <100.00%> (ø)
...tication/3rd Party/ParseSpotify/ParseSpotify.swift	100.00% <100.00%> (ø)

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[cbaker6]

LGTM