vi-mode: reset-prompt if zle is active (TRAPWINCH)

Fixes zle errors when resizing:

  TRAPWINCH:zle: widgets can only be called when ZLE is active

plugins/vi-mode/vi-mode.plugin.zsh

@@ -11,8 +11,7 @@ function zle-line-init() {
 
 # Ensure that the prompt is redrawn when the terminal size changes.
 TRAPWINCH() {
-  zle &&  zle -R
-  zle reset-prompt
+  zle && { zle -R; zle reset-prompt }
 }
 
 zle -N zle-keymap-select