Add quic_framer_process_data_packet_fuzzer, a fuzz test for QuicFramer::ProcessPacket where the packet has a valid public header, is decryptable, and contains random QUIC payload. gfe-relnote: (n/a) Test only. PiperOrigin-RevId: 274791102 Change-Id: I63d55fec8e2a979a06c9e4c74b3095c19ce76c71