Doc: fix some default parameter on records.config

[nozomi1773]

I noticed that some default parameter on the document is incorrect.
I corrected it to the correct value referring to the following source code.

• proxy.config.ssl.server.ticket_key.filename
  

  trafficserver/mgmt/RecordsConfig.cc

  Line 1131 in 1e9e4ed

  {RECT_CONFIG, "proxy.config.ssl.server.ticket_key.filename", RECD_STRING, nullptr, RECU_DYNAMIC, RR_NULL, RECC_NULL, nullptr, RECA_NULL}

• proxy.config.http2.max_header_list_size
  

  trafficserver/mgmt/RecordsConfig.cc

  Line 1322 in 1e9e4ed

  {RECT_CONFIG, "proxy.config.http2.max_header_list_size", RECD_INT, "131072", RECU_DYNAMIC, RR_NULL, RECC_STR, "^[0-9]+$", RECA_NULL}

[randall]

[approve ci]