Even though this is not used yet, it will be a requirement in the
near future for the `RepoProvider` to be the one who decides what
the priority of new repositories is. This will prevent clients of
this provider from specifying wrong priorities that result in gaps
For example, if we accidentally ended up with priorities of
1, 2, 4, and then 5, this would cause problems if the user tried to
drag the second repo to the position of the 4th repo. It is easier
to do these priority shuffles if we can assume that the priorities
are contiguous.
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