Vendored ryu gives warning on some compilers about type limits

[paleolimbot]

This is Ubuntu on aarch64 via Docker:

warning: sedona-geoarrow-c@0.1.0: In file included from src/geoarrow/ryu/common.h:20,
warning: sedona-geoarrow-c@0.1.0:                  from src/geoarrow/ryu/d2s.c:43:
warning: sedona-geoarrow-c@0.1.0: src/geoarrow/ryu/common.h: In function 'decimalLength9':
warning: sedona-geoarrow-c@0.1.0: src/geoarrow/ryu/common.h:36:12: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
warning: sedona-geoarrow-c@0.1.0:    36 |   assert(v >= 0);
warning: sedona-geoarrow-c@0.1.0:       |            ^~
warning: sedona-geoarrow-c@0.1.0: src/geoarrow/ryu/common.h:36:12: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
warning: sedona-geoarrow-c@0.1.0:    36 |   assert(v >= 0);
warning: sedona-geoarrow-c@0.1.0: