Use system-provided ICU libraries

[j20001970]

Building Godot with freetype, libpng, zlib, graphite, harfbuzz as system-provided while leaving icu4c as built-in leads to editor crash when loading GDExtension libraries that uses std::call_once in static initialization.

Please refer to godotengine/godot#91401 for details.

While godotengine/godot#99883 is not merged yet at the time of writing, unofficial Godot builds could change build configuration to use system-provided icu4c libraries, so that it can open minimal reproduction project like https://github.com/j20001970/godot_static_call_once_crash successfully like official build.

[flathubbot]

Started test build 165483

[flathubbot]

Build 165483 successful
To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/148564/org.godotengine.Godot.flatpakref

[Calinou]

Thanks!

[j20001970]

Sorry for converting this to a draft abruptly, I later found a bug when building the engine with system-provided ICU library. Will convert back again if this get addressed upstream.

[flathubbot]

Started test build 167511

[flathubbot]

Build 167511 successful
To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/150608/org.godotengine.Godot.flatpakref