Enable the error_reports plugin by default

The error_reports plugin is the first default plugin with migrations,
so plugin updates during initialization now run migrations against
every configured database - update test_first_run to allow this.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: rtibbles

kolibri/utils/build_config/default_plugins.py

@@ -3,6 +3,7 @@
     "kolibri.plugins.default_theme",
     "kolibri.plugins.device",
     "kolibri.plugins.epub_viewer",
+    "kolibri.plugins.error_reports",
     "kolibri.plugins.html5_viewer",
     "kolibri.plugins.facility",
     "kolibri.plugins.learn",

kolibri/utils/tests/test_main.py

@@ -19,7 +19,8 @@
 # from django.conf import settings
 
 
-@pytest.mark.django_db(transaction=True)
+# initialize() runs plugin migrations against every configured database
+@pytest.mark.django_db(transaction=True, databases="__all__")
 @patch("kolibri.plugins.registry.is_initialized", return_value=False)
 @patch("kolibri.utils.main._upgrades_after_django_setup")
 @patch("kolibri.utils.main.get_version", return_value="")