The version in pkgconfig file is based on `imagequant-sys` crate

[jaudiger]

Following this comment, I was wondering if the version used in the pkgconfig file imagequant.pc should be the one of the crate imagequant and not the one from the crate imagequant-sys.

> cat ./lib/pkgconfig/imagequant.pc
prefix=${pcfiledir}/../..
exec_prefix=${prefix}
libdir=${prefix}/lib
includedir=${prefix}/include

Name: imagequant
Description: Convert 24/32-bit images to 8-bit palette with alpha channel.
Version: 4.1.0
Libs: -L${libdir} -limagequant
Cflags: -I${includedir}
Libs.private: -lgcc_s -lutil -lrt -lpthread -lm -ldl -lc

We're still packaging libimagequant on Brioche, and the latest blocker is how we test the version. As for now, we are comparing the version extracted from the C library with: pkg-config --modversion imagequant to the global version of the project (which is the latest tag). And we hit a mismatch: 4.4.1 != 4.1.0. What would be the recommended way to extract the version of imagequant at build or even runtime ?