use bazel directly during code coverage (#586)
use bazel directly during code coverage (#586)

* use bazel instead of bazelw when generating code coverage
bazelbuild/bazel-buildfarm,bazelbuild/bazel-buildfarm,bazelbuild/bazel-buildfarm,bazelbuild/bazel-buildfarm,bazelbuild/bazel-buildfarm,bazelbuild/bazel-buildfarm,bazelbuild/bazel-buildfarm