Stop tethering when the current user is not allowed to do entitlement check

This commit ensures that EntitlementManager sends the appropriate
error code to the receiver when the current user is not allowed
to perform entitlement check. This error code also listened by
the tethering module, where it would stop tethering when receiving
such error code.

Test: atest TetheringTests:EntitlementManagerTest
Bug: 376792293
Change-Id: I2dd18f9df9ad7cab542f8877b9fc86600c248144
2 files changed