Fails to build dependency 'ragg' when installing

[j-i-l]

This happens during install on MacOS:

https://github.com/furrer-lab/abn/actions/runs/10513612844/job/29782862646

This is unrelated to abn and concerns ragg internals:

 agg/src/agg_font_freetype.cpp:182:35: error: assigning to 'char *' from 'unsigned char *' converts between pointers to integer types where one is of the unique plain 'char' type and the other is not
            tags  = outline.tags  + first;

[j-i-l]

Seems to be a known issue:

r-lib/ragg#170

[j-i-l]

We could either suggest to install an older version of freetype as suggested here or go with the suggested (minimal) changes in the related PR (r-lib/ragg#171)