Move Dokka configs for different modules into a common DokkaConfig.kt file

[jingtang10]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Fixes #1457

Change on top of #1466

Description

• Create DokkaConfig.kt file in /buildSrc
• Upgrade AGP plugin to 7.2.1

Alternative(s) considered
Have you considered any alternatives? And if so, why have you chosen the approach in this PR?

Type
Documentation

Screenshots (if applicable)

Checklist

• I have read and acknowledged the Code of conduct.
• I have read the Contributing page.
• I have signed the Google Individual CLA, or I am covered by my company's Corporate CLA.
• I have discussed my proposed solution with code owners in the linked issue(s) and we have agreed upon the general approach.
• I have run ./gradlew spotlessApply and ./gradlew spotlessCheck to check my code follows the style guide of this project.
• I have run ./gradlew check and ./gradlew connectedCheck to test my changes locally.
• I have built and run the demo app(s) to verify my change fixes the issue and/or does not break the demo app(s).

[codecov]

Codecov Report

Merging #1503 (cd161b8) into master (d715db4) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #1503   +/-   ##
=========================================
  Coverage     74.56%   74.56%           
  Complexity      660      660           
=========================================
  Files           128      128           
  Lines          3995     3995           
  Branches        726      726           
=========================================
  Hits           2979     2979           
  Misses          620      620           
  Partials        396      396           

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[omarismail94]

Just one nit!