Remove unnecessary conditional

It shouldn't be necessary to preserve existing validation errors on an
entry when it is updated via the API.

Author: tekin

app/controllers/v1/submission_entries_controller.rb

@@ -18,7 +18,7 @@ def update
     submission_file = SubmissionFile.find(params[:file_id])
     entry = submission_file.entries.find(params[:id])
     entry.aasm.current_state = submission_entry_params[:status]
-    entry.validation_errors = submission_entry_params[:validation_errors] if submission_entry_params[:validation_errors]
+    entry.validation_errors = submission_entry_params[:validation_errors]
 
     if entry.save
       head :no_content