Add auto-labelling workflow

Author: gorhill

.github/workflows/on-issue-created.yml

@@ -8,23 +8,24 @@ env:
   GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
   GH_REPO: ${{ github.repository }}
   NUMBER: ${{ github.event.issue.number }}
+  BODY: ${{ github.event.issue.body }}
 
 jobs:
   label-chromium:
     runs-on: ubuntu-latest
-    if: contains(github.event.comment.body, 'browser: Chrome') || contains(github.event.comment.body, 'browser: Edge')
+    if: contains(env.BODY, 'browser: Chrome') || contains(env.BODY, 'browser: Edge')
     permissions: write
     steps:
       - run: gh issue edit "$NUMBER" --add-label "Chromium"
   label-firefox:
     runs-on: ubuntu-latest
-    if: contains(github.event.comment.body, 'browser: Firefox')
+    if: contains(env.BODY, 'browser: Firefox')
     permissions: write
     steps:
       - run: gh issue edit "$NUMBER" --add-label "Firefox"
   label-safari:
     runs-on: ubuntu-latest
-    if: contains(github.event.comment.body, 'browser: Safari')
+    if: contains(env.BODY, 'browser: Safari')
     permissions: write
     steps:
       - run: gh issue edit "$NUMBER" --add-label "Safari"