feat: add deployment-wide option to disable workspace sharing (#21172)

Adds `--disable-workspace-sharing` option.

Workspace sharing is disabled by not including user and group ACLs in
the workspace RBAC object, which prevents ACL-based authz.

Closes https://github.com/coder/internal/issues/1072

The commit also adds saving of workspace user/group ACLs in the test DB
data generator.

coderd/coderd.go

@@ -333,6 +333,10 @@ func New(options *Options) *API {
 		})
 	}
 
+	if options.DeploymentValues.DisableWorkspaceSharing {
+		rbac.SetWorkspaceACLDisabled(true)
+	}
+
 	if options.PrometheusRegistry == nil {
 		options.PrometheusRegistry = prometheus.NewRegistry()
 	}