remove extraneous _zsh_nvm_auto_use call

nvm will already be called by the line above (_zsh_nvm_load) so this a) takes longer and b) causes duplicated output in the terminal, e.g.:

Found '/Users/[...]/.nvmrc' with version <9.2.1>
Now using node v9.2.1 (npm v5.5.1)
Found '/Users/[...]/.nvmrc' with version <9.2.1>
Now using node v9.2.1 (npm v5.5.1)

zsh-nvm.plugin.zsh

@@ -102,7 +102,7 @@ _zsh_nvm_lazy_load() {
     eval "$cmd(){
       unset -f $cmds > /dev/null 2>&1
       _zsh_nvm_load
-      [[ "$NVM_AUTO_USE" == true ]] && add-zsh-hook chpwd _zsh_nvm_auto_use && _zsh_nvm_auto_use
+      [[ "$NVM_AUTO_USE" == true ]] && add-zsh-hook chpwd _zsh_nvm_auto_use
       $cmd \"\$@\"
     }"
   done