The refresh-cache step in the refresh-manifests job uses previous master (not newly committed master with new manifests)

[mitchmindtree]

In the last successful refresh-manifests action, this step (which only runs on ubuntu-latest, see #70) introduces the forc-nightly version that has been failing on macos-latest CI recently (see #64).

I would have expected the refresh-cache step that follows to have failed, however on closer inspection the macos-latest fuel-nightly job that followed fetches everything directly from cache and doesn't rebuild anything despite the new manifests.

This indicates that the refresh-cache job is likely using master in the state it was in when the whole workflow began and not the new state of master that was committed by the preceding refresh-manifests job.

This explains why we didn't see any CI failure until the next night's refresh-manifests pass where the refresh-cache step did fail.

It's likely best to address this as a part of #70.