Revert "temp: attempt to force generation to run for iam-policy"

This reverts commit d0cae0d.

Author: zhumin8

sdk-platform-java/.github/scripts/hermetic_library_generation.sh

@@ -121,14 +121,6 @@ python hermetic_build/common/cli/get_changed_libraries.py create \
   --current-generation-config-path="${generation_config}"\
   --force-regenerate-all="${force_regenerate_all}" | tee "${changed_libraries_file}"
 changed_libraries="$(cat "${changed_libraries_file}")"
-# Force run for iam-policy
-if [[ -z "${changed_libraries}" ]]; then
-  changed_libraries="iam-policy"
-else
-  if [[ ! "${changed_libraries}" =~ "iam-policy" ]]; then
-    changed_libraries="iam-policy,${changed_libraries}"
-  fi
-fi
 echo "Changed libraries are: ${changed_libraries:-"No changed library"}."
 
 # run hermetic code generation docker image.