Add gradle build troubleshooting documentation in github_README.md
Add gradle build troubleshooting documentation in github_README.md

Bug: Bug: 175805729
Test: N/A
Change-Id: Iafe5bb4c9d33cd5787986369ac9c8ed60d746725

androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx