Update cxxopts to version 3.2.1 / rev 4 via SR 1161126
    
    https://build.opensuse.org/request/show/1161126
    by user dirkmueller + anag+factory
    - update to 3.2.1:
      * Fix compilation with optional on C++20.
      * Fix unannotated fallthrough.
      * Fix sign conversion with Unicode output.
      * Don't initialize regex in static initialiser.
      * Fix incorrect integer overflow checks.
      * Change quote output to '' to match Windows.
      * Don't split positional arguments by the list delimiter.
      * Order help groups by the order they were added.
    
        short name.