Flag a user
stream-cli chat flag-user --user-id [user-id] --flagged-by-id [user-id] [flags]
# Flag the user 'joe'
$ stream-cli chat flag-user --user-id joe --flagged-by-id admin
-b, --flagged-by-id string [required] ID of the user who flagged the user
-h, --help help for flag-user
-u, --user-id string [required] ID of the user to flag
--app string [optional] Application name to use as it's defined in the configuration file
--config string [optional] Explicit config file path