zfs_delegate_admin: fix: zfs allow cannot parse unknown uid/gid (#5943)

When setting allow permissions for particular users or groups
there will be circumstances when that user is not known to the
host system.

In that case the output of `zfs allow <pool/dataset>`
looks similar to this:

  $ sudo zfs allow tank/test
  ---- Permissions on tank/test ---------------------------------------
  Local+Descendent permissions:
    user (unknown: 1002) hold
    user zfsuser receive

The fix in this commit removes ' (unknown: '+')' from the output
leaving only the uid/gid.

This allows the current parser to continue even if the uid/gid
is not known.

This situation occurs most often when moving a zpool from one system
to another that may not have the same users/groups. Simply adding
permissions to a user/group and then deleting the user/group
from the system will cause this situation to occur.

changelogs/fragments/5943-zfs_delegate_admin-fix-zfs-allow-cannot-parse-unknown-uid-gid.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - zfs_delegate_admin - zfs allow output can now be parsed when uids/gids are not known to the host system (https://github.com/ansible-collections/community.general/pull/5943).

plugins/modules/zfs_delegate_admin.py

@@ -184,6 +184,9 @@ class ZfsDelegateAdmin(object):
             scope = linemap.get(line, scope)
             if not scope:
                 continue
+            if ' (unknown: ' in line:
+                line = line.replace('(unknown: ', '', 1)
+                line = line.replace(')', '', 1)
             try:
                 if line.startswith('\tuser ') or line.startswith('\tgroup '):
                     ent_type, ent, cur_perms = line.split()