Add automatic labels to PRs

Author: Flole998

.github/pr-prefix-labeler.yml

@@ -0,0 +1,2 @@
+"ci": "CI"
+"transifex": "TRANSLATION"

.github/workflows/label-prs.yml

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+name: "Pull Request Labeler"
+on:
+  pull_request_target:
+    types: [opened, synchronize, reopened, edited]
+
+jobs:
+  pr-labeler:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Label the PR
+      uses: gerrymanoim/pr-prefix-labeler@v3
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}