chore: delete dependabot.yml (#5903)

.github/dependabot.yml

@@ -1,22 +0,0 @@
-version: 2
-updates:
-- package-ecosystem: npm
-  directory: "/"
-  schedule:
-    interval: weekly
-    time: "13:00"
-  open-pull-requests-limit: 99
-  ignore:
-  - dependency-name: instantsearch.js
-    versions:
-    - ">= 4.a"
-    - "< 5"
-  - dependency-name: "@primer/css" #TODO: remove when manually upgrading
-    versions:
-    - ">= 16"
-- package-ecosystem: github-actions
-  directory: "/"
-  schedule:
-    interval: weekly
-    time: "13:00"
-  open-pull-requests-limit: 99