feat: add macCatalyst to SPM

[cbaker6]

New Pull Request Checklist

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

Issue Description

macCatalyst isn't specified in Package.swift. The Xcode 13.4 release notes mentions this can cause an issue:

Swift Playgrounds app projects with package dependencies fail to build for Mac Catalyst when a package specifies .iOS(...) in its platforms array in the manifest, but doesn’t specify .macCatalyst(...)

Related issue: #n/a

Approach

Add macCatalyst to Package.swift.

TODOs before merging

• Add entry to changelog

[parse-github-assistant]

Thanks for opening this pull request!

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

[codecov]

Codecov Report

Merging #363 (3d50b73) into main (9a3de84) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #363      +/-   ##
==========================================
- Coverage   87.90%   87.90%   -0.01%     
==========================================
  Files         114      114              
  Lines       12207    12207              
==========================================
- Hits        10731    10730       -1     
- Misses       1476     1477       +1     

Impacted Files	Coverage Δ
Sources/ParseSwift/Objects/ParseObject.swift	84.73% <0.00%> (-0.31%)	⬇️
Sources/ParseSwift/Coding/ParseEncoder.swift	77.77% <0.00%> (+0.11%)	⬆️

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