Merge pull request #998 from humanmade/update-dependabot-remove-v21

Update Dependabot to remove v21 branch

Author: mikelittle

.github/dependabot.yml

@@ -54,14 +54,3 @@ updates:
   - dependency-type: "direct"
   versioning-strategy: "increase"
   target-branch: v22-branch
-- package-ecosystem: composer
-  directory: "/"
-  schedule:
-    interval: weekly
-  ignore:
-    - dependency-name: "wp-phpunit/wp-phpunit"
-  open-pull-requests-limit: 10
-  allow:
-  - dependency-type: "direct"
-  versioning-strategy: "increase"
-  target-branch: v21-branch