Fix malformed XML in test

Remove a stray quote character that is
breaking tests now that the country default
time zone ID is validated.

Bug: 36971201
Test: CTS: run cts -m CtsLibcoreTestCases -t
com.android.timezone.distro.installer.TimeZoneDistroInstallerTest

Change-Id: If99a7f4db8d55d4b522ec24e8da88946d10c7b85