Android NDK is updated from legacy ndk-bundle stuck at unsupported
r22b to LTS NDK r23c (23.2.8568313).
Since GNU binutils have been removed from NDK since r23 (see
https://github.com/android/ndk/wiki/Changelog-r23), ndk-make.sh now
uses TARGET_AR=llvm-ar and uses a workaround for `-lgcc` requirement.
Android command line tools used in the Dockerfile are updated to build
8512546
Preview APKs now use NDK r23c too.