message: added build_test for keyword benchmark.
diff: +load("@bazel_skylib//rules:build_test.bzl", "build_test")
  +
  licenses(["notice"]) # Apache 2.0
  package_group(
  @@ -65,3 +67,8 @@ cc_binary(
  "//tensorflow/lite/schema:schema_fbs",
  ],
  )
  +
  +build_test(
  + name = "build_test",
  + targets = [":keyword_benchmark"],
  +)
  