Update dependency bazelbuild/buildtools to latest version
Update dependency bazelbuild/buildtools to latest version

Included changes:

  - a9f46b2bb3de812fce9f5fe59b29e75d95750aed Fix false positive findings for uninitialized function ar...
  - c9187f6dc6e2604e1fd8b22462eceb8b79c2f3e9 Suppress warnings on unused arguments by @unused comments...
  - 849dfa4e7d1cc0d584eea5a1c3bb51eeb1189537 Allow brackets to describe function arguments in docstrin...

BAZEL_BUILDTOOLS_VERSION_REV_ID: a9f46b2bb3de812fce9f5fe59b29e75d95750aed
Change-Id: I09e10204642172d7d7405d9f3d44d06b5ba43caa

google/copybara,google/copybara,google/copybara