fix(*): bump Android compileSdkVersion to 31

[chloe722]

Description

Hi all,

Currently Android code latest stable version is 1.7.0

This PR is to support Android core 1.7.0 due to the opened issue:
[firebase_core][firebase_analytics][firebase_crashlytics] Build APK failed:verifyReleaseResources'. in Android core 1.7.0 and compileVersion 31 #7723

By upgrading compileSDKVersion to 31 solve the issue since the issue:
AAPT: error: resource android:attr/lStar not found.

lStar which is a system attribute that's new as of API level 31

This is why causing the error and failed to compile and build APK

Related Issues

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Breaking Change

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[chloe722]

@Salakar Hello Salakar
This is my first time send out the PR to FlutterFire. Noticing that I had to sign the CLA.
I've just signed the CLA. I would like to request for the Repository manager who I suppose is you by seeing you are the 1st person listed in the Insight Tab.( If im tagging the right person) to click re-run button next to description as documentation in CLA :)

Thank you for your help!

[russellwheatley]

Hey @chloe722, good work 😄! Is there any chance you could also update the compileSdkVersion version across all the plugins that are listed here which aren't deprecated? We'd prefer to roll these changes inside one PR if possible. Thanks.

[chloe722]

Hi @russellwheatley

I went through all the listing packages and update the compileSdkVersion that aren't at latest 31. PR is ready to check again ! Thank you :)