Make EuiccService un-disable-able.

Disabling the eSIM Manager could leave the device in a bad state, unable
to address the eSIM, and possibly crash due to EuiccConnector failing to
find an LPA to implement EuiccService. So here we do not allow users to
disable this component.

Fixes: 135644632
Test: robotest
Change-Id: Ia4ea48b449f121edaff10531b7c975b09432a8f8