Missing arguments to vctl prints a traceback.

[davidraker]

Calling vctl start without arguments gives a traceback:

(eptron) [dmr@WE44739 Scratch]$ vctl start Traceback (most recent call last): File "/home/dmr/Scratch/eptron/bin/vctl", line 8, in <module> sys.exit(main()) ^^^^^^ File "/home/dmr/Scratch/eptron/lib64/python3.11/site-packages/volttron/client/commands/control.py", line 3028, in main return opts.func(opts) ^^^^^^^^^^^^^^^ File "/home/dmr/Scratch/eptron/lib64/python3.11/site-packages/volttron/client/commands/control.py", line 752, in start_agent act_on_agent("start_agent", opts) File "/home/dmr/Scratch/eptron/lib64/python3.11/site-packages/volttron/client/commands/control.py", line 777, in act_on_agent raise ValueError("Missing argument. Command requires at least one argument.") ValueError: Missing argument. Command requires at least one argument.

To Reproduce
Steps to reproduce the behavior:

1. type "vctl start" then press enter

Expected behavior
Any vctl commands / subcommands should print usage information, possibly with a helpful error message rather than a traceback.
For the case of vctl start, for example, usage information (i.e., the output of "vctl start --help") is:

``
usage: vctl command [OPTIONS] ... start [-h] [--name] [--tag] [--all-tagged] [--uuid] [-c FILE] [--debug] [-t SECS] [--msgdebug MSGDEBUG] [--vip-address ZMQADDR]
[pattern ...]

positional arguments:
pattern UUID or name of agent

options:
-h, --help show this help message and exit
--name filter/search by agent name. value passed should be quoted if it contains a regular expression
--tag filter/search by tag name. value passed should be quoted if it contains a regular expression
--all-tagged filter/search by all tagged agents
--uuid filter/search by UUID (default). value passed should be quoted if it contains a regular expression
-c FILE, --config FILE
read configuration from FILE
--debug show tracebacks for errors rather than a brief message
-t SECS, --timeout SECS
timeout in seconds for remote calls (default: 60)
--msgdebug MSGDEBUG route all messages to an agent while debugging
--vip-address ZMQADDR
ZeroMQ URL to bind for VIP connections
``