Prepare Release using 'release-plan'

Author: github-actions[bot]

release-plan-stderr.txt

@@ -0,0 +1,8 @@
+# Unlabeled Changes
+
+* `@ember/app-blueprint`
+  * [#303](https://github.com/ember-cli/ember-app-blueprint/pull/303) Prepare 7.2 Beta ([@mansona](https://github.com/mansona))
+  * [#300](https://github.com/ember-cli/ember-app-blueprint/pull/300) Update RELEASE.md ([@mansona](https://github.com/mansona))
+
+
+*Cannot plan release until the above changes are labeled*.