Update GitHub Classroom Autograding Workflow

.github/workflows/classroom.yml

@@ -1,11 +1,19 @@
 name: GitHub Classroom Workflow
 
-on: [push]
+on:
+  - push
+  - workflow_dispatch
+
+permissions:
+  checks: write
+  actions: read
+  contents: read
 
 jobs:
   build:
     name: Autograding
     runs-on: ubuntu-latest
+    if: github.actor != 'github-classroom[bot]'
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - uses: education/autograding@v1