ci: add PR quality and coverage gates

backend/engagement/admin.py

@@ -1,3 +1,2 @@
-from django.contrib import admin
 
 # Register your models here.

backend/engagement/tests.py

@@ -1,3 +1,2 @@
-from django.test import TestCase
 
 # Create your tests here.

backend/engagement/views.py

@@ -1,3 +1,2 @@
-from django.shortcuts import render
 
 # Create your views here.