[clang][cli] Ensure plugin args are generated in deterministic order

The '-plugin-arg' command-line arguments are not being generated in deterministic order.

This patch changes the storage from `std::unordered_map` to `std::map` to enforce ordering.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D99879

GitOrigin-RevId: cc26943313def7a985f72eadc7499ac981daabc6
2 files changed