[clang-format] [C++20] [Module] clang-format couldn't recognize partitions
clang-format is butchering modules, this could easily become a barrier to entry for modules given clang-formats wide spread use.
Prevent the following from adding spaces around the : (cf was considering the ':' as an InheritanceColon)
Reviewed By: HazardyKnusperkeks, owenpan, ChuanqiXu
Differential Revision: https://reviews.llvm.org/D114151