prompt_rbenv uses the FAIL_ICON instead of parens to designate missing ruby ver

Author: ChrisBaker97

powerlevel9k.zsh-theme

@@ -1276,7 +1276,7 @@ prompt_rbenv() {
   if [[ -n "$RBENV_VERSION" ]]; then
     "$1_prompt_segment" "$0" "$2" "red" "$DEFAULT_COLOR" "$RBENV_VERSION" 'RUBY_ICON'
   elif [ $commands[rbenv] ]; then
-    local rbenv_version_name="$(rbenv version-name 2>/dev/null || echo "($(rbenv local 2>/dev/null))")"
+    local rbenv_version_name="$(rbenv version-name 2>/dev/null || echo "$(print_icon FAIL_ICON) $(rbenv local 2>/dev/null)")"
     local rbenv_global="$(rbenv global)"
     if [[ "${rbenv_version_name}" != "${rbenv_global}" || "${POWERLEVEL9K_RBENV_PROMPT_ALWAYS_SHOW}" == "true" ]]; then
       "$1_prompt_segment" "$0" "$2" "red" "$DEFAULT_COLOR" "$rbenv_version_name" 'RUBY_ICON'