delete bash_completion in subcommand

There are two "completion" in the subcommand table: bash-completion
and bash_completion. but "bash_completion" is not in help information
and it is repeated with "bash-completion", so delete it.

Change-Id: I5f3bc918a1ce5b6283cc865db4383f128b138d5e
Closes-Bug: #1670123

Author: CrazyLiChunlin

ceilometerclient/shell.py

@@ -117,19 +117,9 @@ def get_subcommand_parser(self, version):
                                                         version, 'shell')
         self._find_actions(subparsers, submodule)
         self._find_actions(subparsers, self)
-        self._add_bash_completion_subparser(subparsers)
 
         return parser
 
-    def _add_bash_completion_subparser(self, subparsers):
-        subparser = subparsers.add_parser(
-            'bash_completion',
-            add_help=False,
-            formatter_class=HelpFormatter
-        )
-        self.subcommands['bash_completion'] = subparser
-        subparser.set_defaults(func=self.do_bash_completion)
-
     def _find_actions(self, subparsers, actions_module):
         for attr in (a for a in dir(actions_module) if a.startswith('do_')):
             # I prefer to be hypen-separated instead of underscores.
@@ -243,7 +233,6 @@ def do_bash_completion(self, args):
                 options.add(option)
 
         commands.remove('bash-completion')
-        commands.remove('bash_completion')
         print(' '.join(commands | options))
 
     @utils.arg('command', metavar='<subcommand>', nargs='?',