[GH] Enable host side tests in GitHub actions
[GH] Enable host side tests in GitHub actions

- Removing setting ANDROID_SDK_ROOT, it is hardcode to a non existent path

Test: tested using https://github.com/androidx/androidx/actions/runs/1451151278

This is an imported pull request from https://github.com/androidx/androidx/pull/277.

Resolves #277
Github-Pr-Head-Sha: b3b6938dc870fe9782ad0d026f5a278abe109285
GitOrigin-RevId: 611b6f04806e6d37c3602501418494f24cc655de
Change-Id: I083efe18ef74955861d7be47e2f7e0a0461bca75

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