Show type as mandatory arg in conn get help

[pau-hedgehog]

Improve UX highlighting <type> as required in the CLI to avoid hitting

core@control-1 ~ $ kubectl fabric conn get
14:56:16 ERR Failed err="failed to get connections: type is required"

core@control-1 ~ $ kubectl fabric conn 
NAME:
   kubectl fabric connection - Connection commands

USAGE:
   kubectl fabric connection command <type> [command options] 

[Frostman]

It currently only have a custom behaviour for management, fabric, vpc-loopback. Everything else is just kubectl get conn, so, you can explicitly list only those 3.

https://github.com/githedgehog/fabric/blob/master/pkg/hhfctl/connection.go

[pau-hedgehog]

This is the best I could get:

pau@fedora:~/fabric$ ./bin/hhfctl connection get --help
NAME:
   hhfctl connection get - Get connections

USAGE:
   hhfctl connection get [command options] <type>

DESCRIPTION:
   Available types: management, fabric, and vpc-loopback

OPTIONS:
   --verbose, -v  verbose output (includes debug) (default: true)
   --help, -h     show help

[Frostman]

@pau-hedgehog I think it's good, let's have it