refacto: Deleting email mentions as there's no emailing system

public/src/api.js

@@ -42,11 +42,11 @@ export async function apiLogin(username, password) {
   });
 }
 
-export async function apiRegister(username, email, password, team) {
+export async function apiRegister(username, password, team) {
   return fetch("/api/auth/register", {
     method: "POST",
     headers: { "Content-Type": "application/json" },
-    body: JSON.stringify({ username, email, password, team }),
+    body: JSON.stringify({ username, password, team }),
   });
 }