util.datamanager: Fix listing of host stores lfs returns the basename of the directory entry, and the check neglected to prefix the data path directory before calling lfs.attribute(), which resulted in checking Prosody's current working directory for the file instead.

For full information on our dependencies, version requirements, and
where to find them, see https://prosody.im/doc/depends

If you have luarocks available on your platform, install the following:

  - luaexpat
  - luasocket
  - luafilesystem
  - luasec