[Automation] Update digest updater workflow to update the hash on the annotation.

[harshad16]

Extension of the issue: #252, This is to automate the hash update on the annotation with digest updater.

Requirements.

• Create a file commit.env in this dir similar to this one. Instead of image, it will be commit. (ex: odh-minimal-notebook-image-commit-n=<hash>)
• grab the commit from here and append the value to the commit.env
• Match the annotation configurable with vars. (Ex: opendatahub.io/notebook-build-commit: $(odh-minimal-notebook-image-commit-n) here)
• Use the param.yaml or create a new file.
• Update the kustomize file to patch value form commit.env to param.yaml.
• use kustomize build manifests/base/ command to check if all these are patching correctly.

[harshad16]

This issue is complete with PR: #375
Thank you for the work 💯