Set up default protection ruleset for default and release branches (#222)

* Set up default protection ruleset for default and release branches

* Drop the branches block from the protection ruleset

No release/* or rel/* branches exist in this repo, and .asf.yaml already
defaults branches to ~DEFAULT_BRANCH when the key is omitted, so the block
only restated the default.

* Do not run Copilot review on drafts or on every push

Copilot review credits are limited; reviewers can trigger a review by hand
when one is wanted.

---------

Co-authored-by: The Apache Software Foundation <root-asf-gitbox-commits@apache.org>

Author: borisstoyanov

.asf.yaml

@@ -30,7 +30,15 @@ github:
   protected_branches:
     main: {}
 
+  rulesets:
+    - name: "Default Branch Protection"
+      type: branch
+      bypass_teams:
+        - root
+      restrict_deletion: true
+      restrict_force_push: true
+
   copilot_code_review:
     enabled: true
-    review_drafts: true
-    review_on_push: true
+    review_drafts: false
+    review_on_push: false