[fix] Invalidate controller views cache when org context changes

When organization context variables are updated,
`bulk_invalidate_config_get_cached_checksum` was called to bust the
Config checksum cache, but `invalidate_controller_views_cache` was
never called. This left the DeviceChecksumView cache stale, so devices
kept receiving the old checksum, never transitioned to `modified`
status, and never pulled the updated configuration.

Fix: also call `invalidate_controller_views_cache` whenever the org
`context` field changes, mirroring the existing behaviour that already
fires this task when an organisation is disabled/enabled.

Fixes openwisp#1070

Author: mn-ram

openwisp_controller/config/base/multitenancy.py

@@ -12,7 +12,7 @@
 
 from .. import settings as app_settings
 from ..exceptions import OrganizationDeviceLimitExceeded
-from ..tasks import bulk_invalidate_config_get_cached_checksum
+from ..tasks import bulk_invalidate_config_get_cached_checksum, invalidate_controller_views_cache
 
 
 class AbstractOrganizationConfigSettings(UUIDModel):
@@ -100,6 +100,7 @@ def save(
             bulk_invalidate_config_get_cached_checksum.delay(
                 {"device__organization_id": str(self.organization_id)}
             )
+            invalidate_controller_views_cache.delay(str(self.organization_id))
 
 
 class AbstractOrganizationLimits(models.Model):