Disable REST default settings testing until #29229 is back-ported

That PR changed the execution path of index settings default to be on the master
until the PR is back-ported the old master will not return default settings.

rest-api-spec/src/main/resources/rest-api-spec/test/indices.put_settings/11_reset.yml

@@ -23,10 +23,15 @@ Test reset index settings:
       indices.get_settings:
         flat_settings: false
   - is_false: test-index.settings.index\.refresh_interval
-  - do:
-      indices.get_settings:
-        include_defaults: true
-        flat_settings: true
-        index: test-index
-  - match:
-      test-index.defaults.index\.refresh_interval: "1s"
+
+# Disabled until https://github.com/elastic/elasticsearch/pull/29229 is back-ported
+# That PR changed the execution path of index settings default to be on the master
+# until the PR is back-ported the old master will not return default settings.
+#
+#  - do:
+#      indices.get_settings:
+#        include_defaults: true
+#        flat_settings: true
+#        index: test-index
+#  - match:
+#      test-index.defaults.index\.refresh_interval: "1s"