chore: revert default to empty, keep script fallback referencing env vars directly

Author: shenxianpeng

action.yml

@@ -232,14 +232,14 @@ inputs:
       Git username for the auto-fix commit.
       Defaults to the value of ``$GITHUB_ACTOR``.
       Only used when ``auto-fix`` is ``true``.
-    default: '${{ env.GITHUB_ACTOR }}'
+    default: ''
     required: false
   auto-fix-git-email:
     description: |-
       Git email for the auto-fix commit.
       Defaults to the value of ``$GITHUB_ACTOR_ID+$GITHUB_ACTOR@users.noreply.github.com``.
       Only used when ``auto-fix`` is ``true``.
-    default: '${{ env.GITHUB_ACTOR_ID }}+${{ env.GITHUB_ACTOR }}@users.noreply.github.com'
+    default: ''
     required: false
   jobs:
     description: |