ci: disable auto updating github actions (#8)

Disable updating GitHub actions automatically because the workflows are generated using `cargo dist`

Author: jeroenvervaeke

.github/dependabot.yml

@@ -22,16 +22,3 @@ updates:
         applies-to: version-updates
         patterns:
           - "*"
-
-  # Enable version updates for GitHub Actions
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "weekly"
-      day: "monday"
-      time: "09:00"
-    open-pull-requests-limit: 5
-    commit-message:
-      prefix: "chore(deps)"
-    labels:
-      - "dependencies"