pgagroal-cli incompatible (or incomplete) options

[fluca1978]

Using pgagroal 019ea11, while working on #253 I discovered by accident that the following seems to work:

$ pgagroal-cli status -U luca -P secret
Status:              Running
Active connections:  0
Total connections:   1
Max connections:     4
Segmentation fault (core dumped)

and also something more interesting that could reveal the issue of the segmentation fault:

$ pgagroal-cli details -U luca -P secret
...
Connection    0:     Free            2022-06-20 07:07:24        21     pgbench pgbench 
Connection    1:     Not initialized                                     
Connection    2:     Not initialized                                     
Connection    3:     Not initialized                                     
free(): invalid pointer
Aborted (core dumped)

The point here is that the -P and -U options should not be taken into account at all when not providing a remote connection information. So the pgagroal-cli program should warn the user that she has mixed arguments.
I suspect also that the core dumped is related to some remote connection information not properly allocated and that is going to be freed.