[CLI] Bad help text

[Jeremy Freudberg]

As an example, consider "cluster scale" command:

```
usage: openstack dataprocessing cluster scale [-h]
                                              [-f {html,json,json,shell,table,value,yaml,yaml}]
                                              [-c COLUMN]
                                              [--max-width <integer>]
                                              [--print-empty] [--noindent]
                                              [--prefix PREFIX]
                                              [--instances <node-group-template:instances_count> [<node-group-template:instances_count> ...]]
                                              [--json <filename>] [--wait]
                                              <cluster>
```

In fact, the positional argument <cluster> must come before --instances. Otherwise it complains about not enough arguments. Interestingly, adding --wait can make the ordering more flexible.

Probably further investigations needed, as the issue may apply to other CLI commands.

[Luigi Toscano (ltoscano)]

Something similar to https://bugs.launchpad.net/python-saharaclient/+bug/1560557 ?

[Jeremy Freudberg (jfreud)]

Yes, same bug.