The use of `sprintf()` was causing compiler warnings on Apple's version
of Clang. This replaces those uses with `fmt::format_to_n()` from
libfmt, which is safer and silences those warnings.
Additionally, the format string given to `printf()` in debugging
functions for the path template unit tests was also causing warnings due
to type mismatch (long long vs long). This replaces those with
`fmt::print()`, which infers the correct type on its own, silencing
those warnings.
Pull Request: https://projects.blender.org/blender/blender/pulls/138660
0b97a13eaa