Add ability to import projects

[nbolten]

This pull request adds the ability to import projects, such as with tofu import incus_project.project1 project1. I added tests as well using the tests used for networks as a reference.

My Go is rusty so let me know if I should improve this PR in any way!

[stgraber]

Hey @nbolten, we use the DCO on this project, so require commits to have a Signed-off-by: Firstname Lastname <email> line.

You can usually add that with:

• git commit --amend -s
• git push --force

@lxc/incus-terraform it'd probably be a good idea to add a CONTRIBUTING.md similar to the Incus one to cover that bit. Also probably cleanup README.md to drop that outdated list of contributors (the release announcements include an up to date one) and link to CONTRIBUTING.md

[nbolten]

Added the Signed-off-by line!

[mdavidsen]

@lxc/incus-terraform it'd probably be a good idea to add a CONTRIBUTING.md similar to the Incus one to cover that bit. Also probably cleanup README.md to drop that outdated list of contributors (the release announcements include an up to date one) and link to CONTRIBUTING.md

Yeah, that's probobly something that should be done. I'll make a PR for further discussion on the topic

[adamcstephens]

We should make sure that any changes to functionality include the associated documentation. @nbolten would you be willing open a new PR updating the docs? You can use this for inspiration: https://github.com/terraform-lxd/terraform-provider-lxd/pull/410