Change the permissions of PR Labeler (#1040)

Author: nakamura-to

.github/workflows/pr-labeler.yml

@@ -4,14 +4,19 @@ on:
   pull_request:
     types: [opened]
 
+permissions:
+  contents: read
+
 jobs:
   pr-labeler:
+    permissions:
+      contents: read # for TimonVS/pr-labeler-action to read config file
+      pull-requests: write # for TimonVS/pr-labeler-action to add labels in PR
     runs-on: ubuntu-latest
     timeout-minutes: 30
 
     steps:
       - uses: TimonVS/pr-labeler-action@v4
         with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
           configuration-path: .github/pr-labeler.yml
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}