Add findAll query

[cbaker6]

Adds the ability to findAll objects.

• Add findAll async and publisher
• Added ParseSwift.deleteObjectiveCKeychain() to remove iOS Objective-C Keychain from device
• Documentation
• Testcases
• Add playground example for findAll and relative time query
• Prepare for new release

[codecov]

Codecov Report

Merging #118 (90c597b) into main (1d3d1d6) will increase coverage by 0.15%.
The diff coverage is 87.50%.

@@            Coverage Diff             @@
##             main     #118      +/-   ##
==========================================
+ Coverage   80.73%   80.88%   +0.15%     
==========================================
  Files          65       65              
  Lines        5528     5593      +65     
==========================================
+ Hits         4463     4524      +61     
- Misses       1065     1069       +4     

Impacted Files	Coverage Δ
...ParseSwift/Objects/ParseInstallation+combine.swift	100.00% <ø> (ø)
...urces/ParseSwift/Objects/ParseObject+combine.swift	100.00% <ø> (ø)
Sources/ParseSwift/Objects/ParseUser+combine.swift	92.98% <ø> (ø)
Sources/ParseSwift/Types/Query.swift	90.68% <74.35%> (-0.10%)	⬇️
Sources/ParseSwift/Objects/ParseInstallation.swift	78.62% <100.00%> (+0.16%)	⬆️
Sources/ParseSwift/Objects/ParseObject.swift	77.27% <100.00%> (+0.76%)	⬆️
Sources/ParseSwift/Objects/ParseUser.swift	81.52% <100.00%> (-0.05%)	⬇️
Sources/ParseSwift/Parse.swift	100.00% <100.00%> (ø)
Sources/ParseSwift/Types/Query+combine.swift	100.00% <100.00%> (ø)
... and 2 more

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