fix: improve codable's

[cbaker6]

New Pull Request Checklist

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

Issue Description

Improve the ability of the internal AnyCodable to encode Encodable.

Related issue: #n/a

Approach

Add more test cases.

TODOs before merging

• Add tests

[parse-github-assistant]

Thanks for opening this pull request!

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

[codecov]

Codecov Report

Merging #352 (cf8ff55) into main (8b90507) will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #352      +/-   ##
==========================================
+ Coverage   87.31%   87.35%   +0.04%     
==========================================
  Files         114      114              
  Lines       12207    12209       +2     
==========================================
+ Hits        10658    10665       +7     
+ Misses       1549     1544       -5     

Impacted Files	Coverage Δ
Sources/ParseSwift/Coding/AnyDecodable.swift	27.47% <ø> (ø)
Sources/ParseSwift/Coding/AnyEncodable.swift	52.29% <100.00%> (+2.88%)	⬆️
Sources/ParseSwift/Objects/ParseObject.swift	84.88% <0.00%> (-0.46%)	⬇️
Sources/ParseSwift/LiveQuery/ParseLiveQuery.swift	73.63% <0.00%> (+0.58%)	⬆️

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