🐛(fix) fix body scroll when a modal is opened

It was possible to scroll the body when a modal is opened, it was
cutting the visibility of the modal, and was simply weird.

Fixes #263

packages/react/src/hooks/usePrevious.ts

@@ -0,0 +1,19 @@
+import { useEffect, useRef } from "react";
+
+/**
+ * Hook which stores the previous value of a component prop or state.
+ * https://usehooks.com/usePrevious/
+ *
+ * @param value
+ */
+const usePrevious = <T>(value: T): T => {
+  const previous = useRef<T>(value);
+
+  useEffect(() => {
+    previous.current = value;
+  }, [value]);
+
+  return previous.current;
+};
+
+export default usePrevious;