Memory leak reusing a pn_transport_t for multiple connections

==24281== 94 bytes in 12 blocks are definitely lost in loss record 1 of 2
==24281== at 0x4C2CB6B: malloc (vg_replace_malloc.c:299)
==24281== by 0x4E4AD33: pn_strndup (util.c:152)
==24281== by 0x4E5913E: pn_bytes_strdup (transport.c:1160)
==24281== by 0x4E5913E: pn_do_open (transport.c:1200)
==24281== by 0x4E51267: pni_dispatch_action (dispatcher.c:74)
==24281== by 0x4E51267: pni_dispatch_frame (dispatcher.c:116)
==24281== by 0x4E51267: pn_dispatcher_input (dispatcher.c:135)
==24281== by 0x4E579AB: pn_input_read_amqp (transport.c:2567)
==24281== by 0x4E57A57: transport_consume (transport.c:1823)
==24281== by 0x4E5B175: pn_transport_process (transport.c:2952)
==24281== by 0x401E21: fcd_read (fuzz-connection-driver.c:212)
==24281== by 0x401F2B: LLVMFuzzerTestOneInput (fuzz-connection-driver.c:94)
==24281== by 0x401A65: main (StandaloneFuzzTargetMain.c:37)