Refresh conntrack entry timeout

Needed because the BPF maps offloads IPv4 traffic. The kernel can't
trace the offloaded traffic to keep the conntrack entry.

Bug: 190783768
Test: atest TetheringCoverageTests
Original-Change: https://android-review.googlesource.com/1566871
Merged-In: Idbcf686c9b2124b192944156ac5111be741744fb
Change-Id: Idbcf686c9b2124b192944156ac5111be741744fb
2 files changed