Revert "Adding flag com.android.wm.shell.enable_taskbar_on_phones to RELEASE_CONFIG_TRUNKFOOD_STAGING."

This reverts commit 0fbed184d2f112aeb6c687b6c2a97dbf4d35803b.

Reason for revert: <IPotential culprit for b/360386010  - verifying through ABTD before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.>

Change-Id: Ide5d8de693ae9c7e0d206f10e33da3e29f533e22