Fixed edit username and password

src/main/webapp/js/settings.js

-document.getElementById("newUsername").value = sessionStorage.getItem("username");
+let usernameVariable = document.getElementById("newUsername");
+let passwordVariable = document.getElementById("newPassword");
+
+usernameVariable.value = sessionStorage.getItem("username");
+passwordVariable.value = sessionStorage.getItem("password");
+
 document.getElementById("cancelButton").addEventListener("click", function(){
     window.location.href = "../app.html";
 });
@@ -8,7 +13,7 @@ document.getElementById("cancelButton").addEventListener("click", function(){
  */
 function editUser (event) {
     event.preventDefault();
-    let newInformation = {};
+    let newInformation = {"username": usernameVariable.value, "password": passwordVariable.value};
 
    fetch('../api/user/'+sessionStorage.getItem("userId"), {
            method: "PUT",