Remove clear datastore function (#13088)

src/client/java/teammates/client/scripts/sql/SeedDb.java

@@ -470,21 +470,6 @@ private Account createAccount(String googleId, String accountName, String email)
         return account;
     }
 
-    /**
-     * Clears all entities in the data store if re-seeding is needed.
-     */
-    private void clearDataStore() {
-        ofy().delete().entities(ofy().load().type(Account.class).list()).now();
-        ofy().delete().entities(ofy().load().type(AccountRequest.class).list()).now();
-        ofy().delete().entities(ofy().load().type(Course.class).list()).now();
-        ofy().delete().entities(ofy().load().type(CourseStudent.class).list()).now();
-        ofy().delete().entities(ofy().load().type(FeedbackQuestion.class).list()).now();
-        ofy().delete().entities(ofy().load().type(FeedbackResponse.class).list()).now();
-        ofy().delete().entities(ofy().load().type(FeedbackResponseComment.class).list()).now();
-        ofy().delete().entities(ofy().load().type(FeedbackSession.class).list()).now();
-        ofy().delete().entities(ofy().load().type(Notification.class).list()).now();
-        log("Finish deleting all entities");
-    }
 
     private void log(String logLine) {
         System.out.println(String.format("Seeding database: %s", logLine));
@@ -497,7 +482,6 @@ protected void persistData() {
         // Persisting basic data bundle
         DataBundle dataBundle = getTypicalDataBundle();
         try {
-            clearDataStore();
             // logic.persistDataBundle(dataBundle);
             persistAdditionalData();
         } catch (Exception e) {