Enable pre-commit workflow with manual dispatch trigger

.github/workflows/pre-commit.yml

@@ -1,16 +1,17 @@
 # disabled. We might run it manually if needed.
-#name: pre-commit
-#
-#on:
+name: pre-commit
+
+on:
+  workflow_dispatch:
 #  pull_request:
 #  push:
 #    branches: [main]
-#
-#jobs:
-#  pre-commit:
-#    runs-on: ubuntu-latest
-#    steps:
-#      - uses: actions/checkout@v3
-#      - uses: actions/setup-python@v5
-#      # SEE https://github.com/pre-commit/action
-#      - uses: pre-commit/action@v3.0.1
+
+jobs:
+  pre-commit:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v5
+      # SEE https://github.com/pre-commit/action
+      - uses: pre-commit/action@v3.0.1