fmtlib: update to 10.1.0

>From the release information on GitHub:

  * Optimized format string compilation resulting in up to 40% speed up
    in compiled format_to and ~4x speed up in compiled format_to_n on a
    concatenation benchmark
  * Optimized storage of an empty allocator in basic_memory_buffer
  * Added formatters for proxy references to elements of
    std::vector<bool> and std::bitset<N>
  * Fixed an ambiguous formatter specialization for containers that look
    like container adaptors such as boost::flat_set
  * Fixed compilation when formatting durations not convertible from
    std::chrono::seconds
  * Made the formatter specialization for char* const-correct
  * Made {} and {:} handled consistently during compile-time checks
  * Disallowed passing temporaries to make_format_args to improve API
    safety by preventing dangling references
  * Improved the compile-time error for unformattable types
  * Improved the floating-point formatter
  * Fixed handling of precision for long double larger than 64 bits
  * Made floating-point and chrono tests less platform-dependent
  * Removed the remnants of the Grisu floating-point formatter that has
    been replaced by Dragonbox in earlier versions
  * Added throw_format_error to the public API
  * Made FMT_THROW assert even if assertions are disabled when compiling
    with exceptions disabled
  * Added support for the ? format specifier to std::filesystem::path
    and made the default unescaped for consistency with strings
  * Made format_as and std::filesystem::path formatter work with exotic
    code unit types
  * Deprecated the wide stream overload of printf
  * Removed unused basic_printf_parse_context.
  * Improved RTTI detection used when formatting exceptions
  * Improved compatibility with VxWorks7
  * Improved documentation
  * Improved build and CI configurations
  * Fixed various warnings and compilation issues

(khorben)