ASHWANI PANDEY Thank you for sharing the solution. It will greatly help others facing similar issues and looking for a solution. Microsoft Q&A has policy: Accept an answer that question authors cannot accept their own answers and hence I am posting your answer in case you like to accept.
Resolution:
The issue was using GITHUB_TOKEN
to deploy container App in registryPassword
which didn't have right permissions and hence it was denied. You had created a new token with read permissions and the issue was resolved.