This adds a Revert two-step button to the JobVersions component for
not-current versions, which redirects to the overview on success. It
checks the job version before and after reversion to mitigate the edge
case where reverting to an otherwise-identical version has no effect, as
discussed in #10337.
It uses existing facilities for handling other errors and disabling the
button when permissions are lacking.
When sorting by size, directories are sorted by name, as size
isn’t displayed.
This includes a change to the positioning of sort arrows for all tables,
moving them closer to the text, because in some cases, the arrows
for right-aligned columns were ambiguously positioned.
