Temporary workaround for Kokoro bug

`git status` on Kokoro has started reporting all symlinks as dirty.
This breaks is_repo_dirty checks in our build scripts. Temporarily
work around the problem by ignoring dirtiness of submodules as symlinks
are only present in third_party/linux/ and prebuilts/.

Bug: 152398137
Change-Id: Id412d766b988c114b4a6af33db2defaae612a7a2
1 file changed