TT#25312 make conference_pin editable for subscribers

Change-Id: I625a026ad745ea8d20d9ef0840963e89ec15c315
(cherry picked from commit 7e2490f1d0)

db_scripts/diff/15371.down

@@ -0,0 +1,3 @@
+USE provisioning;
+
+UPDATE voip_preferences SET expose_to_customer=0 WHERE attribute='conference_pin';

db_scripts/diff/15371.up

@@ -0,0 +1,3 @@
+USE provisioning;
+
+UPDATE voip_preferences SET expose_to_customer=1 WHERE attribute='conference_pin';