Log Message:
devel/difftastic: update to 0.55.0

0.55 (released 1st February 2024)
Parsing
 - Added support for Objective-C and VHDL.
 - Files starting with <?xml are now parsed as XML.
 - Fixed a munmap_chunk(): invalid pointer crash on parsing some large files,
   particularly JSON.

Display
 - The default display width for tabs has changed to 4.
 - Fixed an issue where difftastic would sometimes output literal tabs rather
   than respecting the display width for tabs.

Build
 - difftastic now requires Rust 1.65 to build.