FEAT: run workflow on "update pip constraints" comment (#252)

* BREAK: remove concurrecy from workflow
  This is in case multiple comments are made about different topics

src/repoma/.github/workflows/requirements.yml

@@ -1,10 +1,9 @@
 name: Requirements
 
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
-  cancel-in-progress: true
-
 on:
+  issue_comment:
+    types:
+      - created
   pull_request:
     branches:
       - main

src/repoma/check_dev_files/update_pip_constraints.py

@@ -5,6 +5,10 @@
 - https://github.com/ComPWA/update-pre-commit
 """
 
+from __future__ import annotations
+
+from glob import glob
+
 from repoma.check_dev_files.github_workflows import remove_workflow, update_workflow
 from repoma.errors import PrecommitError
 from repoma.utilities import CONFIG_PATH, REPOMA_DIR
@@ -43,7 +47,9 @@ def overwrite_workflow(workflow_file: str, cron_schedule: str) -> None:
         )
         yaml = create_prettier_round_trip_yaml()
         expected_data = yaml.load(expected_workflow_path)
+        paths: list[str] = expected_data["on"]["pull_request"]["paths"]
         expected_data["on"]["schedule"][0]["cron"] = cron_schedule
+        expected_data["on"]["pull_request"]["paths"] = [p for p in paths if glob(p)]
         workflow_path = CONFIG_PATH.github_workflow_dir / workflow_file
         if not workflow_path.exists():
             update_workflow(yaml, expected_data, workflow_path)