Bug: `rstuf artifact repository set` allows set default as inexistent repository

[kairoaraujo]

What happened?

The rstuf artifact repository set command allows user to set a default repository that doesn't exist in your configuration.

What steps did you take?

> rstuf artifact repository show 
local-tuf
> rstuf artifact repository set inexisting-tuf
Current repository changed to inexisting-tuf

What behavior did you expect?

rstuf artifact repository set should only allow a configured repository.

Relevant log output

Code of Conduct

• I agree to follow this project's Code of Conduct

[imranur-rahman]

Hi, I would like to work on this issue since I am trying to learn more about the repository and contribute to it. This seems like a good issue for me to start with.

The solution would be to update the set function with proper validation for repositories (e.g., if the requested repository is not already configured, it should raise an error). I made a commit with this change: link. I would like your guidance on working with this issue @kairoaraujo . Please let me know if we need to add anything else here. Thanks!

[kairoaraujo]

Hi, I would like to work on this issue since I am trying to learn more about the repository and contribute to it. This seems like a good issue for me to start with.

The solution would be to update the set function with proper validation for repositories (e.g., if the requested repository is not already configured, it should raise an error). I made a commit with this change: link. I would like your guidance on working with this issue @kairoaraujo . Please let me know if we need to add anything else here. Thanks!

Hi @imranur-rahman, thank you again for your contribution.
If you see, there is a PR already opened to this issue #808.

This opened PR is just missing the tests. Maybe you can interact with @Abhijeet213 to complete this PR.
We are about to cut a new release, but still have time to include this contribution there.

[Abhijeet213]

Added Another Pull Request With Tests

Thanks To @imranur-rahman , @kairoaraujo ...