docs: specify cd-command in fish shell wrapper (#135)

docs/quick-start.md

@@ -42,7 +42,7 @@ function yy
 	set tmp (mktemp -t "yazi-cwd.XXXXXX")
 	yazi $argv --cwd-file="$tmp"
 	if set cwd (command cat -- "$tmp"); and [ -n "$cwd" ]; and [ "$cwd" != "$PWD" ]
-		cd -- "$cwd"
+		builtin cd -- "$cwd"
 	end
 	rm -f -- "$tmp"
 end