fix: Remove listeners in GoogleMap.cameraEvents(): Flow<CameraEvent> implementation

[ychescale9]

Fixes #80.

• Removed the added listeners in the awaitClose within the GoogleMap.cameraEvents(): Flow<CameraEvent> implementation.
• Removed the unnecessary inline keyword as the function has no parameters of function types.

Also made a couple of unrelated changes (let me know if you want them in a separate PR):

• Also bumped coroutines to version 1.3.8
• changed kotlin-stdlib-jdk7 to kotlin-stdlib as no Java 7 APIs are used.

Ran ./gradlew assemble check locally.

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[ychescale9]

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[codecov]

Codecov Report

Merging #82 into master will not change coverage.
The diff coverage is 0.00%.

@@          Coverage Diff           @@
##           master     #82   +/-   ##
======================================
  Coverage    0.00%   0.00%           
======================================
  Files          28      28           
  Lines         172     186   +14     
  Branches       26      26           
======================================
- Misses        172     186   +14     

Impacted Files	Coverage Δ
...main/java/com/google/maps/android/ktx/GoogleMap.kt	0.00% <0.00%> (ø)

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[arriolac]

Thanks for sending us a PR! I have one stylistic comment, other than that, it looks good to me.

[googlemaps-bot]

🎉 This PR is included in version 2.1.1 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀