Remove docs about sync back workflow

In favour of docs in the script itself

Author: henrymercer

pr-checks/readme.md

@@ -9,42 +9,6 @@ to one of the files in this directory.
 1. Install https://github.com/casey/just by whichever way you prefer.
 2. Run `just update-pr-checks` in your terminal.
 
-### If you don't want to intall `just`
+### If you don't want to install `just`
 
 Manually run each step in the `justfile`.
-
-## Sync-back automation
-
-When Dependabot updates action versions in the generated workflow files (`.github/workflows/__*.yml`), 
-the sync-back automation ensures those changes are properly reflected in the source templates.
-
-The sync-back script automatically detects all actions used in generated workflows and preserves
-version comments (e.g., `# v1.2.3`) when syncing versions between files.
-
-### Running sync-back manually
-
-To sync action versions from generated workflows back to source templates:
-
-```bash
-# Dry run to see what would be changed
-python3 pr-checks/sync_back.py --dry-run --verbose
-
-# Actually apply the changes
-python3 pr-checks/sync_back.py
-```
-
-The sync-back script automatically updates:
-- Hardcoded action versions in `pr-checks/sync.py`
-- Action version references in template files in `pr-checks/checks/`
-
-Regular workflow files are updated directly by Dependabot and don't need sync-back.
-
-This ensures that the `verify-pr-checks.sh` test always passes after Dependabot PRs.
-
-### Testing
-
-The sync-back script includes comprehensive tests that can be run with:
-
-```bash
-python3 pr-checks/test_sync_back.py -v
-```