Revert "ApnSettingsActivity shows the ActionBar"

This reverts commit 5a7f5a09310e75d2e13fb0d4e7dda99f0b4662ef.

Reason for revert: seems to cause b/331379466 according to the culprit range search

Change-Id: I6ab2474864d43a1a8bcb50de5bc9ab5c0ac08f4e
Bug: 331379466
1 file changed