Revert "Disable karborclient until a fixed version is released"

Fixed karborclient has been released. The problem only exists
in karborclient 0.4.0 and the current version is 0.6.0.

This reverts commit 99a502b.

Change-Id: Ie28fa1e0502792c87e68ab1c009b3349c739892b

Author: amotoki

doc/source/cli/plugin-commands.rst

@@ -58,11 +58,11 @@ ironic-inspector
 .. list-plugins:: openstack.baremetal_introspection.v1
    :detailed:
 
-.. karbor
-.. ------
-.. bug 1705258: Exclude karborclient 0.4.0 until a fixed version is released.
-.. .. list-plugins:: openstack.data_protection.v1
-..    :detailed:
+karbor
+------
+
+.. list-plugins:: openstack.data_protection.v1
+   :detailed:
 
 mistral
 -------