Update zsh and bash completion scripts.

This is to update the zsh and bash completion script for
23367.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

contrib/completion/bash/docker

@@ -2853,7 +2853,7 @@ _docker_volume_ls() {
 _docker_volume_rm() {
 	case "$cur" in
 		-*)
-			COMPREPLY=( $( compgen -W "--help" -- "$cur" ) )
+			COMPREPLY=( $( compgen -W "--force -f --help" -- "$cur" ) )
 			;;
 		*)
 			__docker_complete_volumes

contrib/completion/zsh/_docker

@@ -1360,6 +1360,7 @@ __docker_volume_subcommand() {
         (rm)
             _arguments $(__docker_arguments) \
                 $opts_help \
+                "($help -f --force)"{-f,--force}"[Force the removal of one or more volumes]" \
                 "($help -):volume:__docker_volumes" && ret=0
             ;;
         (help)