Checking the fields selector array length in a better way

src/scripts/coopstarter.js

@@ -672,7 +672,7 @@ function listenToInputChangeOnResourceCreation(originalForm) {
     }
   });
   
-  if (isValid.length == 13) {
+  if (isValid.length == resourcesFieldsSelector.length) {
     submitInput.disabled = false;
     submitInput.classList.remove('disabled');
   } else {
@@ -691,7 +691,7 @@ function listenToInputChangeOnMentorAccountCompletion(originalForm) {
     }
   });
 
-  if (isValid.length == 6) {
+  if (isValid.length == mentorFieldsSelector.length) {
     submitInput.disabled = false;
     submitInput.classList.remove('disabled');
   } else {