Full docker Url support

[serdarozerr]

Current behavior

The function ParseDockerRef() failing to parse when user provides tag and sha256 together in the URL, see the example:

User URL:
docker.io/library/redis:latest@sha256:e118d023acaee5cf13471ead39f68416ad6172ff0899f3257ce1481cd2b28a6a

How the function is parse:
hostname= "docker.io"
path= "library/redis:latest@sha256"
tag= "e118d023acaee5cf13471ead39f68416ad6172ff0899f3257ce1481cd2b28a6a"

Desired behavior

How it should to be:
hostname= "docker.io"
path= "library/redis"
tag= "latest@sha256e118d023acaee5cf13471ead39f68416ad6172ff0899f3257ce1481cd2b28a6a"

Another solution would be the tag or sh256 can be droped from the URL to be compliant with OCI specifications

Affected Version

commit id =629abfec55850d8a32cf13120af71fa21bf74ea3