offloaded some apps.lyric.views responsibilities to new Celery depend fn in .tasks; core.celery created for celery config; CELERY_BROKER_URL added to .settings & throughout project; some lyric view IT responsibility now accordingly covered by task UT domain

src/apps/lyric/tests/unit/test_tasks.py

@@ -0,0 +1,16 @@
+from django.test import SimpleTestCase
+from unittest import mock
+
+from apps.lyric.tasks import send_login_email_task
+
+
+class SendLoginEmailTaskTest(SimpleTestCase):
+    @mock.patch("apps.lyric.tasks.requests.post")
+    def test_sends_mail_via_mailgun(self, mock_post):
+        send_login_email_task("discoman@example.com", "http://example.com/login?token=abc123")
+        self.assertEqual(mock_post.called, True)
+        data = mock_post.call_args.kwargs["data"]
+        self.assertEqual(data["subject"], "A magic login link to your Dashboard")
+        self.assertEqual(data["from"], "adman@howdy.earthmanrpg.com")
+        self.assertEqual(data["to"], "discoman@example.com")
+        self.assertIn("http://example.com/login?token=abc123", data["text"])