Bash completion supports multiple stacks in `stack rm`

Signed-off-by: Harald Albers <github@albersweb.de>

contrib/completion/bash/docker

@@ -4078,11 +4078,7 @@ _docker_stack_rm() {
 			COMPREPLY=( $( compgen -W "--help" -- "$cur" ) )
 			;;
 		*)
-			local counter=$(__docker_pos_first_nonflag)
-			if [ $cword -eq $counter ]; then
-				__docker_complete_stacks
-			fi
-			;;
+			__docker_complete_stacks
 	esac
 }