DynamicDenylistManager shall not exist

Remove DynamicDenylistManager to avoid its conflicting behavior
with our firewall. This stops the resetting of firewall policies
on boot and for other reasons. The user is in control of these
policies and doesn't need them to be unexpectedly reset.

Issue: calyxos#2211
Test: Manual: Turn off Background network access for any app. Then,
in Firewall, turn off another toggle like Wi-Fi. Reboot, and check
the toggles. Background network access and Wi-Fi should still be off.
Change-Id: Ie62ddfa3a893c9adf5d4fd0c8670235a5a51e03f