Azure Linux tags do not match directory structure

[MichaelSimons]

See the src folder structure policy: https://github.com/dotnet/dotnet-buildtools-prereqs-docker/blob/main/README.md#source-folder-structure. This has a long standing policy of the repo. It helps in navigating the repo to find the Dockerfile given a tag. There is no test that enforces this.

Example:

          "platforms": [
            {
              "dockerfile": "src/azurelinux/3.0/net9.0/crossdeps-llvm/amd64",
              "os": "linux",
              "osVersion": "azurelinux3.0",
              "tags": {
                "azurelinux-3.0-crossdeps-llvm-net9.0$(FloatingTagSuffix)": {},
                "azurelinux-3.0-crossdeps-llvm-net9.0-local": {
                  "isLocal": true
                }
              }
            }

There are two options to correct this:

• Rename the tag to: azurelinux-3.0-net9.0-crossdeps-llvm-amd64
• Restructure the folder path to: src/azurelinux/3.0/crossdeps-llvm/amd64/net9.0

I understand the desire to group all netx.y related Dockerfiles under a folder.

My recommendation if the decision is to make a change to the tagging, add the new tag for a period of time until all usage is migrated to the new tag and then remove the old tag.

[MichaelSimons]

cc @sbomer, @mthalman, @jkoritzinsky

[MichaelSimons]

Related to #1035

[sbomer]

I have no objection to renaming the tags to azurelinux-3.0-net9.0-crossdeps-llvm-amd64.

[richlander]

If we're going to rename the tags (which is fine), we need to ensure we catch all the cases in runtime (and anywhere else they are used).