Support force pushing to repositories using the Refspec format

[Racer159]

Is your feature request related to a problem? Please describe.

Now that Zarf supports git refspecs we should support the + prefix to allow force push behavior to be specified.

Describe the solution you'd like

Using the + syntax of git refspecs to enable force pushing of git repos in the airgap on Zarf deploy.

The changes should be primarily here: https://github.com/defenseunicorns/zarf/blob/git-kiss/src/internal/packager/git/push.go along with relevant docs: https://github.com/defenseunicorns/zarf/tree/git-kiss/examples/git-data and tests: https://github.com/defenseunicorns/zarf/blob/git-kiss/src/test/e2e/22_git_and_flux_test.go

Describe alternatives you've considered

We could use URI syntax to introduce something like ?force=true but this may be confusing for those familiar with git and may be misleading since that never is passed to an http server.

Additional context

This is a continuation of the work done in #1404

[corang]

What's the plan on where force-pushing will be specified? I would argue against putting it in the zarf.yaml as I see this as more of a deploy-time issue. Some end user consuming a package might not know if a repo that's in the package had a force push done to it and if it did they then have to go back across the airgap, build a new package, and carry it across again. I'd prefer a prompt on fast-forward failure or an argument you can pass to zarf when deploying (maybe a zarf.toml thing?). At the very least I think that functionality could be in addition to be able to set it in the zarf.yaml at create time.

[corang]

I'm gonna pick this up with the path of adding a deploy time flag that changes the git push strategy

[Jneville0815]

@corang is this still in the works?

[corang]

Not by me