OSDOCS-4396: remove restricted channel group option

Author: bmcelvee

modules/rosa-create-objects.adoc

@@ -77,9 +77,6 @@ $ rosa create cluster --cluster=<cluster_name> | <cluster_id> [arguments]
 |--cluster
 |Required: The name or ID (string) of the cluster. When used with the `create cluster` command, this argument is used to generate a sub-domain for your cluster on `openshiftapps.com`.
 
-|--channel-group
-|The channel group (string) is the name of the group where this image belongs, for example `stable` or `fast`. Default: `stable`
-
 |--compute-machine-type
 |The instance type (string) for the compute nodes. Determines the amount of memory and vCPU that are allocated to each compute node.
 

modules/rosa-list-objects.adoc

@@ -405,15 +405,6 @@ List all of the OpenShift versions that are available for creating a cluster.
 $ rosa list versions [arguments]
 ----
 
-.Arguments
-[cols="30,70"]
-|===
-|Option |Definition
-
-|--channel-group
-|Lists only versions from the specified channel group (string). Default: `stable`
-|===
-
 .Optional arguments inherited from parent commands
 [cols="30,70"]
 |===