bug#69617: guix go import fails on some version tags

[Ryan Barber]

In some cases the "guix import go" command fails when attempting to
checkout the source for a module using a tag which does not exist in
the repo.

Upon further investigation, I have found guix/import/go.scm will use
the version string as tag. While this works most of the time, some
module vendors use a different tagging scheme. For example, the
azure-sdk-for-go repository contains many modules and the version tags
are namespaced by module name.

The tag for version v1.3.0 of azure-sdk-for-go/sdk/storage/azblob is
storage/azblob/v1.3.0.

$ curl -s 
'https://proxy.golang.org/github.com/!azure/azure-sdk-for-go/sdk/storage/azblob/@v/v1.3.0.info'
| jq
{
  "Version": "v1.3.0",
  "Time": "2024-02-12T16:20:44Z",
  "Origin": {
    "VCS": "git",
    "URL": "https://github.com/Azure/azure-sdk-for-go";,
    "Subdir": "sdk/storage/azblob",
    "Ref": "refs/tags/sdk/storage/azblob/v1.3.0",
    "Hash": "d5dfa9296a115cc5094b14198b7114a64a490994"
  }
}

I have a patch to fix this, but I would like to discuss the approach
before submitting it. Should I reply to this bug report with the
patch?

Here is the backtrace when attempting to run import on storage/azblob

$ guix import go github.com/Azure/azure-sdk-for-go/sdk/storage/azblob
Backtrace:
          14 (primitive-load "/home/rfb/.config/guix/current/bin/guix")
In guix/ui.scm:
   2324:7 13 (run-guix . _)
  2287:10 12 (run-guix-command _ . _)
In guix/scripts/import.scm:
     80:6 11 (guix-import . _)
In ice-9/boot-9.scm:
  1752:10 10 (with-exception-handler _ _ #:unwind? _ # _)
In guix/scripts/import/go.scm:
   116:29  9 (_)
In ice-9/exceptions.scm:
   406:15  8 (go-module->guix-package* . _)
In ice-9/boot-9.scm:
  1752:10  7 (with-exception-handler _ _ #:unwind? _ # _)
In guix/import/go.scm:
   532:19  6 (go-module->guix-package "github.com/Azure/azure-sdk-f…" …)
In guix/git.scm:
    295:4  5 (update-cached-checkout _ #:ref _ #:recursive? _ # _ # _ …)
   281:19  4 (resolve _)
In git/reference.scm:
     60:8  3 (_ _ _)
In git/bindings.scm:
     77:2  2 (raise-git-error _)
In ice-9/boot-9.scm:
  1685:16  1 (raise-exception _ #:continuable? _)
  1683:16  0 (raise-exception _ #:continuable? _)

ice-9/boot-9.scm:1683:16: In procedure raise-exception:
Git error: reference 'refs/tags/v1.3.1' not found