Fix android user creation during init

Init was crashing with error:

    django.db.utils.IntegrityError: (1062, "Duplicate entry 'android' for key 'client_id'")

See
https://discuss.overhang.io/t/reset-password-email-sent-but-activation-email-dont/690/4

CHANGELOG.md

@@ -4,6 +4,7 @@ Note: Breaking changes between versions are indicated by "💥".
 
 ## Unreleased
 
+- [Bugfix] Fix android user creation during init
 - [Bugfix] Fix undefined settings in k8s scripts, such as `createuser`
 
 ## v10.0.7 (2020-06-22)

tutor/templates/hooks/lms/init

@@ -4,12 +4,16 @@ echo "Loading settings $DJANGO_SETTINGS_MODULE"
 
 ./manage.py lms migrate
 
+# Delete obsolete credentials for Android application
+./manage.py lms shell -c 'from oauth2_provider.models import get_application_model
+get_application_model().objects.filter(name="android").exclude(user__username="login_service_user").delete()'
 # Create oauth credentials for Android application
 ./manage.py lms create_dot_application \
     --client-id android \
     --client-secret {{ ANDROID_OAUTH2_SECRET }} \
     --grant-type password \
     --public \
+    --update \
     android \
     login_service_user