Add a Dependabot ignore directive for downstream repository

Co-authored-by: Nick <50747025+mcdonnnj@users.noreply.github.com>

Author: jsf9k

.github/dependabot.yml

@@ -29,6 +29,7 @@ updates:
     # ignore:
     #   # Managed by cisagov/skeleton-ansible-role
     #   - dependency-name: ansible
+    #   - dependency-name: ansible-core
     package-ecosystem: pip
     schedule:
       interval: weekly