[script][vuln] Add prefix aliasing and fix doc

bob/pad/base/script/vuln.py

@@ -3,9 +3,11 @@
 import click
 import pkg_resources
 from click_plugins import with_plugins
+from bob.extension.scripts.click_helper import AliasedGroup
+
 
 @with_plugins(pkg_resources.iter_entry_points('bob.vuln.cli'))
-@click.group()
+@click.group(cls=AliasedGroup)
 def vuln():
-  """Presentation Attack Detection related commands."""
+  """Vulnerability analysis related commands."""
   pass