art: Refactor buildbot-build.sh to run test targets directly

`build-art-host-gtests` and `build-art-target-gtests` are PHONY targets
that only copy dependencies to `$(HOST_OUT)`. They are not required for
the execution of `art-run-test-host-data`, `art-run-test-jvm-data`, and
`art-run-test-target-data`.

These test targets (art-run-test-host-data, art-run-test-jvm-data, and
art-run-test-target-data) have been converted to Android.bp and are
now independent. Therefore, they can be executed directly without first
building `build-art-host-gtests` and `build-art-target-gtests`.

This change modifies art/tools/buildbot-build.sh to directly execute
these Android.bp test targets, removing the unnecessary building of
`build-art-host-gtests` and `build-art-target-gtests`.

This refactoring streamlines the build process in CI, reducing
redundant build steps and potential points of failure.

Bug: 388015096
Bug: 395776750
Bug: 395776112
Test: CIs
Change-Id: If68b5ccaf9c715053e9e798b00f53fc414840d93
1 file changed