Handle git ls-remote asking for authentication

[cam72cam]

If a repository is removed or made private, git ls-remote will hang asking for user authentication and break the bumper.

[serdardalgic]

One question, AFAICS, git ls-remote is called directly using os/exec. Did you folks consider using go-git package for calling git commands in the registry? I wonder if there is any reason not to use that. It looks like quite an active project, and takes care of the error handling for most of the cases.

[cam72cam]

@Yantrio had used it extensively in similar work recently and was running into some extremely odd issues and inconsistencies.

[Yantrio]

I did use it and it was extremely flakey for no reason at all. It was not stable enough for me to be confident with using it here. However I'm happy if we re-visit this in the future.

[cam72cam]

Alternatively we could try using https://api.github.com/repos/:org/:repo/git/refs/tags

ex: https://api.github.com/repos/eda-dev-test/terraform-aws-test/git/refs/tags

[cam72cam]

cmesh@atavisage:~/OpenTOFU/registry-stable/src$ time curl -s https://api.github.com/repos/eda-dev-test/terraform-aws-test/git/refs/tags -o /dev/null 

real    0m0.565s
user    0m0.044s
sys     0m0.012s
cmesh@atavisage:~/OpenTOFU/registry-stable/src$ time git ls-remote https://github.com/eda-dev-test/terraform-aws-test/ > /dev/null 

real    0m0.315s
user    0m0.045s
sys     0m0.025s

With the overhead of the fork/dup/etc.. this might actually be faster.

[cam72cam]

It's also worth noting that this is not a problem for github actions. git ls-remote is unable to poll the term for user input and fails. It's mostly an issue when running it locally.