refine comments on counter variable

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

Author: daixtrose

polymorphism/test/src/test_consume.cpp

@@ -47,7 +47,9 @@ int main()
           };
 
     "[modern mock]"_test = [] {
-        static constexpr auto EXPECTED_COOLFEATURE_CALLS = 2; // Called once for initial value and once for modification
+        static constexpr auto EXPECTED_COOLFEATURE_CALLS = 2; // coolFeature() is called:
+                                                             // 1. During initial value check (line 54)
+                                                             // 2. During side effect verification (line 68)
         given("I have a an mock that adheres to a concept") = [] {
             mocking::Mock impl;