message: workaround ssize_t in Hera also in Nerve_GIC
diff: # include <gudhi/Bottleneck.h>
  #elif __has_include(<hera/bottleneck.h>)
  # define GUDHI_GIC_USE_HERA 1
  +# ifdef _MSC_VER
  +// https://github.com/grey-narn/hera/issues/3
  +// ssize_t is a non-standard type (well, posix)
  +# include <type_traits>
  +# include <cstdlib>
  +using ssize_t = std::make_signed_t<std::size_t>;
  +# endif
  # include <hera/bottleneck.h>
  #endif
  