project: Remove dead code now the build system is determined by reflex-platform
project: Remove dead code now the build system is determined by reflex-platform

(cherry picked from commit 58a49c47becfbc78c16d13af2345358720fd80e5)

ryantrinkle/try-reflex,reflex-frp/reflex-platform,reflex-frp/reflex-platform,reflex-frp/reflex-platform