Fix deadlock in DPMS

Dont hold lock while calling in to NetworkPolicyManagerService in
removeAdminArtifacts
Bug: 223382458
Test: atest com.android.server.devicepolicy.DevicePolicyManagerTest#testForceRemoveActiveAdmin_nonShellCallerWithPermission
      atest com.android.server.devicepolicy.DevicePolicyManagerTest#testForceRemoveActiveAdmin_ShellCaller

Change-Id: I1e83201211678df203908a52759858fa7dd44e5b
1 file changed