Fix failing BluetoothPbapSimVcardManagerTest

testGetSIMPhonebookNameList_orderByAlphabet was failing since
the test does not set the local phone name in the service.

This CL fixes it, and also recovers the static variable
(local phone name) after the test ends.

Bug: 258075245
Test: atest BluetoothPbapSimVcardManagerTest
Change-Id: I4a8f3fd9e2a18ba1e626febef0e0ef3588e5f835