Make a pcapng file, not pcap

.gitignore

@@ -34,4 +34,5 @@ __pycache__
 *.vcd
 *.fst.*
 results.xml
-html
\ No newline at end of file
+html
+*.pcapng
\ No newline at end of file

hw/super6502_fpga/src/sub/network_processor/sim/cocotb/tests/tcp_test.py

@@ -57,7 +57,7 @@ def ip_to_hex(ip: str) -> int:
 
 @cocotb.test()
 async def test_simple(dut):
-    pktdump = PcapWriter("tcp.pcap", append=True, sync=True)
+    pktdump = PcapWriter("tcp.pcapng", append=True, sync=True)
 
 
     tb = TB(dut)