Update readme

Use correct formxtra link.
hace 1 año · 1cd34d515c
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@

 Use forms with or without client-side JavaScript--no code duplication required!

 Powered by [formxtra](https://code.modal.sh/modal-soft/formxtra).
 Powered by [formxtra](https://code.modal.sh/TheoryOfNekomata/formxtra).

 ## Why?