Use regex to check for email on RegisterPage

src/utils/Misc.js

@@ -0,0 +1,8 @@
+export const isEmail = input => {
+    // Taken from https://emailregex.com
+    const result = input.match(
+        //eslint-disable-next-line
+        /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/,
+    );
+    return result;
+};