Resolve #3422537 "Increment or remove"

Closes #3422537

.gitlab-ci.yml

-# cspell:ignore codequality Micheh micheh webide updatedb stylelintrc
+# cspell:ignore codequality Micheh micheh webide updatedb stylelintrc unshallow
 
 ################
 # Drupal GitLabCI template.
@@ -401,6 +401,7 @@ default:
       fi;
     - cd core
     - corepack enable
+    - git diff ${CI_MERGE_REQUEST_TARGET_BRANCH_SHA:-$CI_MERGE_REQUEST_DIFF_BASE_SHA} --name-only 2>1 > /dev/null || (echo "Warning, cannot find changed files, converting to full clone." & (git fetch --unshallow --quiet && echo "Fetch successful."))
     - git diff ${CI_MERGE_REQUEST_TARGET_BRANCH_SHA:-$CI_MERGE_REQUEST_DIFF_BASE_SHA} --name-only | sed "s_^_../_" | yarn run spellcheck:core --no-must-find-files --file-list stdin
 
 '📔 Validatable config':