ecr push with Ignore Tag Immutability errors not working anymore

[rohit-tandon]

Actual behavior
kaniko image push with --push-ignore-immutable-tag-errors isn't working because it depends upon error message from AWS and aws has changed the message.

Kaniko logic to catch tag immutability error depends upon part error message returned by the aws/ecr,
it expects aws error message to contain cannot be overwritten because the repository is immutable,
but at some point aws has updated message to cannot be overwritten because the tag is immutable, notice the change from repository to tag.
https://github.com/GoogleContainerTools/kaniko/blob/v1.23.2/pkg/executor/push.go#L301
https://github.com/GoogleContainerTools/kaniko/blob/v1.23.2/pkg/executor/push.go#L71

Preferable this logic can be changed to use "ImageTagAlreadyExistsException" thrown by aws-cli instead of depending upon error message. https://docs.aws.amazon.com/AmazonECR/latest/userguide/image-tag-mutability.html

Expected behaviour
push-ignore-immutable-tag-errors should catch and ignore the error. Preferably

To Reproduce
Steps to reproduce the behavior:

1. Set an AWS ECR repo as immutable
2. push an image to repo using kaniko push /kaniko/executor --dockerfile ./Dockerfile --context . --cleanup --push-ignore-immutable-tag-errors --destination
3. push the same image again
4. error pushing image: failed to push to destination ecr-destination:tag: TAG_INVALID: The image tag already exists in the repository and cannot be overwritten because the tag is immutable.

Additional Information

Triage Notes for the Maintainers

Description	Yes/No
Please check if this a new feature you are proposing
Please check if the build works in docker but not in kaniko
Please check if this error is seen when you use --cache flag
Please check if your dockerfile is a multistage dockerfile