[clang] [llvm] [MC/DC] Refactor: Introduce `ConditionIDs` as `std::array<2>` (PR #81221)

[Alan Phipps via cfe-commits]

================
@@ -217,6 +217,9 @@ class CounterExpressionBuilder {
 
 using LineColPair = std::pair<unsigned, unsigned>;
 
+using MCDCConditionID = unsigned int;
+using MCDCConditionIDs = std::array<MCDCConditionID, 2>;
----------------
evodius96 wrote:

is `std::array<>` better than `std::pair<>` when it only has two elements?

https://github.com/llvm/llvm-project/pull/81221