Extend timeout for requesting tethered interface

Extend the timeout to lower the EthernetTetheringTest flaky.

Besides, also explicitly exempt entitlement check in
EtetherntTetheringTest because it do not test tethering upstream
currently. Thus, the tests would not be interrupted by entitlement
check if test SIM is entitlement required.

Bug: 156713866
Test: TetheringCoverageTests, CtsTehteringTest

Merged-In: I45e8e8d737486def9d0de8943ec7f09ca0942a0b
Change-Id: I45e8e8d737486def9d0de8943ec7f09ca0942a0b