chore: custom primary key dependency update

[HuiSF]

Issue #, if available:

Description of changes:

• update generated many-to-many models using the latest codegen
• bump amplify-android to 1.37.2 (new version should be available on 8/15/2022)

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[codecov-commenter]

Codecov Report

Merging #2036 (9e1c533) into main (e841596) will increase coverage by 0.27%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #2036      +/-   ##
==========================================
+ Coverage   47.84%   48.11%   +0.27%     
==========================================
  Files         373      378       +5     
  Lines       10873    10978     +105     
==========================================
+ Hits         5202     5282      +80     
- Misses       5671     5696      +25     

Flag	Coverage Δ
android-unit-tests	∅ <ø> (∅)
flutter-unit-tests	38.22% <ø> (ø)
ios-unit-tests	89.16% <ø> (-0.68%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
..._pinpoint_ios/example/ios/Runner/AppDelegate.swift	0.00% <0.00%> (ø)
...e/ios/unit_tests/MockAnalyticsCategoryPlugin.swift	15.38% <0.00%> (ø)
.../ios/unit_tests/amplify_flutter_exampleTests.swift	94.59% <0.00%> (ø)
...ios/example/ios/unit_tests/AtomicResultTests.swift	87.75% <0.00%> (ø)
...y_flutter_ios/example/ios/Runner/AppDelegate.swift	0.00% <0.00%> (ø)