fix example_project in Django 4.0

Author: PetrDlouhy

example_project/urls.py

@@ -1,13 +1,13 @@
 from django.contrib import admin
-from django.conf.urls import include, url
+from django.urls import include, path
 from django.views.generic import TemplateView
 
 admin.autodiscover()
 
 urlpatterns = [
-    url(r'experiments/', include('experiments.urls')),
-    url(r'admin/', admin.site.urls),
-    url(r'^$', TemplateView.as_view(template_name="test_page.html"), name="test_page"),
-    url(r'^goal/$', TemplateView.as_view(template_name="goal.html"), name="goal"),
+    path('experiments/', include('experiments.urls')),
+    path('admin/', admin.site.urls),
+    path('', TemplateView.as_view(template_name="test_page.html"), name="test_page"),
+    path('goal/', TemplateView.as_view(template_name="goal.html"), name="goal"),
 ]