Dear Maintainer,

Package libkeymancore-dev needs libicu-dev according to the pkg-config file
via Requires.private:

prefix=/usr
includedir=${prefix}/include
libdir=${prefix}/lib/x86_64-linux-gnu

Name: keyman_core
Description: Keyman processor for KMN keyboards.
Version: 17.0.274
Requires.private: icu-uc, icu-i18n
Libs: -L${libdir} -lkeymancore
Cflags: -I${includedir} -I${includedir}/keyman

However, the debian package libkeymancore-dev does not explicitly depends on
libicu-dev, rendering FTBFS when invoking pkg-config to use libkeymancore-dev:

(example in CMake:)