Revert "Allowlist more of system/timezone"

This reverts commit da03b080.

Reason for revert: This was previously reverted in aosp/2510617 due to b/275666961, which spawned b/276416537 and b/276416485 that Cole and I are working on now. Given that the root causes are still being actively resolved, I believe this will cause the test (b/275666961) to fail again.

Change-Id: I69e756f823f920610a832a1fc88b415074c0f488