improve faketcp, handle tcp GSO correctly (#1708)

Current implementation falsely drop GSO-merged tcp packet, and cause unexpected packet loss.

.github/workflows/core.yml

@@ -203,7 +203,7 @@ jobs:
 
       # Copied and slightly modified from @lmq8267 (https://github.com/lmq8267)
       - name: Build Core & Cli (X86_64 FreeBSD)
-        uses: vmactions/freebsd-vm@v1
+        uses: vmactions/freebsd-vm@670398e4236735b8b65805c3da44b7a511fb8b27
         if: ${{ endsWith(matrix.TARGET, 'freebsd') }}
         env:
           TARGET: ${{ matrix.TARGET }}