Rename repository from "SlicerMRunner" to "SlicerMHubRunner"

[jcfr]

To ensure the GitHub repository name is consistent with the extension name, consider the following steps:

• Rename from SlicerMRunner to SlicerMHubRunner
• Update scm_url in https://github.com/Slicer/ExtensionsIndex/blob/main/MHubRunner.json

[LennyN95]

Hey @jcfr., great point!

We originally intended to keep the uppercase M branding... MHub, MRunner, etc.
But we also realized that MRunner isn't associated with MHub, so SlickerMHubRunner or, maybe even better, just SlicerMHub shall be the extension's name.

I'm developing a new version, which I'd like to replace the old one with, that should then be joined with the renamed (or a new) repository.

Thanks for the comment and your eagle eye ;)

[jcfr]

Thanks for the follow-up 🙏

Moving forward, there would no issues renaming the extension.

In the meantime, would appreciate if you could integrate the following pull request required to restore successful packaging&upload of the extension:

• COMP: Fix extension packaging updating project name to match extension name #5