Update to new upstream release 5.5.

Credits to Greg for a thorough preparation of the update,
much appreciated with a huge thank you.

Release announcement:
https://rawtherapee.com/blog/rawtherapee-5.5-released

A selection of news (read the announcement for more, and screenshots):

• stripe artifact removal for phase detection auto-focus (PDAF) for Nikon Z6, Z7, and various Sony cameras
• improved support for Canon mRaw
• new Shadows/Highlights tool
• constrast threshold masks to filter effects by high/low detail regions
• new color toning methods
• new soft light tool
• ICC profile creator
• new "flexible" tone curve type
• improved lensfun chromatic aberration correction

While here, since the abort-on-exit bug persists,
wrap rawtherapee in a script that runs ulimit -c 0,
and make note of it in pkg-message. References:

• https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=205370
• https://github.com/Beep6581/RawTherapee/issues/3636

PR: 234153
Submitted by: Greg V <greg@unrelenting.technology>