Make the deletion of old versions more robust (#2712)
Make the deletion of old versions more robust (#2712)

When using the VFS Swift backend, the deletion of old versions can reuse
code for emptying the trash: it makes several calls to Swift, with a bit
of waiting if needed and a retry logic.
nono/cozy-stack,nono/cozy-stack,nono/cozy-stack,nono/cozy-stack,nono/cozy-stack