Fix algorithm tests to ensure no lingering sockets

Lingering TCP sockets appear to be causing testUpdatePolicy to fail due
to policies attached to TCP sockets in TIME_WAIT. This patch sets
SO_LINGER on the algorithm tests' sockets, forcing them to shutdown
cleanly, and synchronously.

Bug: 74071662
Test: Ran on common 3.18, 4.4 with parallel_tests.sh 20 10
Change-Id: Ie9ab9b7672cc2ce8309ed871eeee09ec8128aac9