show example of mod install syntax?

[judell]

Currently, steampipe mod install --help is as below.

I do this infrequently enough to always need to go to the docs to remind myself that the command I'm looking for is like this:

steampipe mod install github.com/turbot/steampipe-mod-aws-thrifty

Could we include an example like that?

steampipe mod install --help
Install one or more mods and their dependencies.

Usage:
  steampipe mod install [flags]

Flags:
      --dry-run   Show which mods would be installed/updated/uninstalled without modifying them
  -h, --help      Help for install
      --prune     Remove unused dependencies after installation is complete (default true)

Global Flags:
      --cloud-host string           Steampipe Cloud host (default "cloud.steampipe.io")
      --cloud-token string          Steampipe Cloud authentication token
      --install-dir string          Path to the Config Directory (defaults to ~/.steampipe) (default "~/.steampipe")
      --schema-comments             Include schema comments when importing connection schemas (default true)
      --workspace string            Path to the workspace working directory (DEPRECATED: please use workspace-chdir)
      --workspace-chdir string      Path to the workspace working directory

[pskrbasu]

Completed in #3821