auib_import should either warn about using branch or check for updates on branch

[Alex2772]

At the moment, auib_import does not track updates on branches. It's seems unclear to people because they assume by specifying a branch aui boot will somehow keep the dependency up-to-date.

I propose 2 possible solutions:

1. Create a warning (maybe error) message that the user specified a branch name instead of static reference (i.e., commit hash or tag). The team would experience a lot of errors because of outdated dependencies and thus they would possibly switch from branch to static referencing.
2. Detect if it is a branch, and if it is, track dependencies' remotes and update them accordingly. Warning message is optional. Possible configure slowdown, as aui boot would constantly check for updates on dependencies whose version is specified by a branch.

Personally, I prefer static referencing instead of branches because you 100% sure that if you open the project in the future you would not encounter compile error messages because some of dependencies received updates. This is also how git submodules work, and I'm sure there's the reason on why they forcing to use static references. On the other hand, specifying the branch name is handier and easier when you just tinkering with projects.

I've a lot of projects utilizing auib_import, and they are able to compile today just because they referencing the older versions of the dependencies.

[Alex2772]

This moment spams with false positives. @qWeth unfortunately I can't make a stable reproducer at the moment