chore: Update CODEOWNERS file [skip ci] (#2128)

Correct syntax of CODEOWNERS file per https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-code-owners

Author: palpatim

.github/CODEOWNERS

@@ -1,3 +1,3 @@
 # The amplify-ui team is marked as required reviewers for all pull requests to main.
 # See https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-code-owners
-@aws-amplify/amplify-ui
+*     @aws-amplify/amplify-ui