Escape double quotes when printing ABSOLUTE_TIME field

This regression was introduced by the commit e5353bf1198d6abf748de78084ff64f597f13663 done for bug 10081

Bug: 10213
Change-Id: I3925a47ef13055f10f49fa9fefd022731746fbb8
Reviewed-on: https://code.wireshark.org/review/2572
Reviewed-by: Pascal Quantin <pascal.quantin@gmail.com>
Petri-Dish: Pascal Quantin <pascal.quantin@gmail.com>
Reviewed-by: Evan Huus <eapache@gmail.com>
Reviewed-by: Michael Mann <mmann78@netscape.net>