fix doc to display show_command (#6860)

doc/command_guidelines.md

@@ -81,7 +81,7 @@ The following are standard names and behavioral descriptions for CRUD commands c
 - `CREATE` - standard command to create a new resource. Usually backed server-side by a PUT request. 'create' commands should be idempotent and should return the resource that was created.
 - `UPDATE` - command to selectively update properties of a resource and preserve existing values. May be backed server-side by either a PUT or PATCH request, but the behavior of the command should always be PATCH-like. All `update` commands should be registered using the `generic_update_command` helper to expose the three generic update properties. `update` commands MAY also allow for create-like behavior (PATCH) in cases where a dedicated `create` command is deemed unnecessary. `update` commands should return the updated resource.
 - `SET` - command to replace all properties of a resource without preserving existing values, typically backed server-side by a PUT request. This is used when PATCH-like behavior is deemed unnecessary and means that any properties not specifies are reset to their default values. `set` commands are more rare compared to `update` commands. `set` commands should return the updated resource.
-- `SHOW` - command to show the properties of a resource, backed server-side by a GET request. All `show` commands should be registered using the `generic_show_command` helper to ensure `404(Not Found)` is always returning an exit code of 3.
+- `SHOW` - command to show the properties of a resource, backed server-side by a GET request. All `show` commands should be registered using the `show_command` or `custom_show_command` helpers to ensure `404(Not Found)` is always returning an exit code of 3.
 - `LIST` - command to list instances of a resource, backed server-side by a GET request. When there are multiple "list-type" commands within an SDK to list resources at different levels (for example, listing resources in a subscription vice in a resource group) the functionality should be exposed by have a single list command with arguments to control the behavior. For example, if `--resource-group` is provided, the command will call `list_by_resource_group`; otherwise, it will call `list_by_subscription`.
 - `DELETE` - command to delete a resource, backed server-side by a DELETE request. Delete commands return nothing on success.