HDDS-11990. Use arity in decommission subcommands

[adoroszlai]

What changes were proposed in this pull request?

Reduce code duplication in decommission and maintenance subcommands.

• Specify arity to require at least one parameter, instead of checking explicitly.
• Extract duplicated "list of host names" parameter and logic.
• Reuse "show errors" logic.

https://issues.apache.org/jira/browse/HDDS-11990

How was this patch tested?

Tested in ozone-topology env:

$ ozone admin datanode maintenance
Missing required parameter: '<host name>'
Usage: ozone admin datanode maintenance [-hV] [--force] [--end=<endInHours>]
                                        [-id=<scmServiceId>] [--scm=<scm>]
                                        <host name>...
Put a datanode into Maintenance Mode
      <host name>...       One or more host names separated by spaces. To read
                             from stdin, specify '-' and supply the host names
                             separated by newlines.
      --end=<endInHours>   Automatically end maintenance after the given hours.
                             By default, maintenance must be ended manually.
      --force              Forcefully try to decommission the datanode(s)
  -h, --help               Show this help message and exit.
      -id, --service-id=<scmServiceId>
                           ServiceId of SCM HA Cluster
      --scm=<scm>          The destination scm (host:port)
  -V, --version            Print version information and exit.


$ ozone admin datanode maintenance - <<EOF
> 18f367dac6f6
> 2f5e52c1f56b
> EOF
Entering maintenance mode on datanode(s):
18f367dac6f6
2f5e52c1f56b


$ ozone admin datanode maintenance asdf
Entering maintenance mode on datanode(s):
asdf
Error: asdf: asdf: Name or service not known
Some nodes could not start the maintenance workflow

[smengcl]

lgtm. Thanks @adoroszlai for the improvement