Catch all the PHPCS errors only on changed files (https://github.com/woocommerce/woocommerce-blocks/pull/10402)

* Commit a php lint warning

* Add param to show php warnings

* Print exit code

* Test

* test 2

* Add back cs2pr

* Add checkstyle

* Remove exit code

* Test without report

* Add checkstyle

* Fix php

* Test changed files

* Print changed files

* Introduce error

* More errors

* Fix errors

* Test

* Test all cases

* Fix php lint errors

* Rename readme

* Show all files

* Test new action

* Test

* Try other actions

* Add errors

* Remove actions

* More errors

* Fix git diff

* Fix all php errors

* Remove git fetch

* Add error

* Fix error and action

plugins/woocommerce-blocks/.github/workflows/php-coding-standards.yml

@@ -60,5 +60,8 @@ jobs:
             - name: Log PHPCS debug information
               run: phpcs -i
 
-            - name: Run PHPCS on all files
-              run: phpcs ./src -n --report=checkstyle | cs2pr
+            - name: Run PHPCS on all changed files
+              run: |
+                git fetch origin trunk
+                changes=$(git diff --name-only origin/trunk..HEAD | tr '\n' ' ')
+                phpcs ${changes} -q --report=checkstyle | cs2pr