http-backend: http backend lock error return LockError instead of generic error

[nvanheuverzwijn]

This PR make the http backend respect the lock-timeout flag. Currently, there is no way to wait for a lock when using http backend.
With this PR :

1. Http backend now returns a LockError instead of a generic Error whenever the http post to lock the state returns HTTP code StatusConflict (409) or StatusLocked (423).
2. Http backend will now respect correctly the lock-timeout flag.

[hashicorp-cla]

All committers have signed the CLA.

[antoinedeschenes]

mentioned here as well #27670 (comment)

[crw]

Thanks for this submission! I cannot commit to having this PR reviewed due to the general hold on backend reviews (see CONTRIBUTING.md#state-storage-backends. That said, I will bring this up in triage and see if this can be reviewed. Thanks again for your submission!

[nvanheuverzwijn]

@crw Hey Craig, thanks for the reply, really appreciate it! FYI, this is more of a bug fix than an enhancement if that changes anything for the review process.

In any case, thank you for your time!

[alisdair]

Thanks for this fix! If you know of a related GitHub issue, please let me know so I can close it.

[github-actions]

Reminder for the merging maintainer: if this is a user-visible change, please update the changelog on the appropriate release branch.

[nvanheuverzwijn]

@alisdair Hey! Thank you for merging!
I searched for relevant keywords in the issues and I didn't find any. I guess people that had this problem just shrugged it off or found a workaround or it's just not used that much.
Anyway, cheers!

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active contributions.
If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.