Check Xtbpf readings after making http traffic

It is needed to aquire more information about bpf program status
to debug test464XlatTcpStats flakiness.

Thus, this change parses counters of xtbpf hooks to ensure
xtbpf program status when testing.

Test: atest NetworkStackIntegrationTests:NetworkStatsIntegrationTest \
      --rerun-until-failure 100
Bug: 292156770
Change-Id: I91d86ef1d200d2920bc1cf635eb39af3c62fcf67
2 files changed