The branches master and develop ofthe MOOSE_MISSIONS repository are not mergable.
So we should spilt them into two repos in the same way like MOOSE_DOCS and MOOSE_DOCS_DEVELOP.
Both should oly have a master branch.
Advantages:
- Checkout on disk on parrallel
- Less hard disk space compared to checkout MOOSE_MISSIONS twice (like I do now)
- Easy fix for missing scheduled GitHub Workflow to update Moose.lua in mission files (works no only for master)