Inline rbc-run script

The board configuration already had this inlined, and the addition
of a separate script makes it harder to follow what's happening.

Bug: 280685526
Test: ./build/bazel/ci/rbc_dashboard.py --quick aosp_arm64-userdebug
Change-Id: Ib76c4a46932ae81d84f854fbee5b0453266d6497