Fix unreachable code in Unity on fully covered switch statements

 The clang compiler warns here with -Wunreachable-code
 The enum's switch statement covers all cases, so default is unused
 Leave the break in the code as a comment, to be more clear
 The history is this default case was added in f6bb7162 - compiler warning.
 Then the break was added in c6dc96f3.

src/unity.c

@@ -775,7 +775,7 @@ void UnityAssertFloatSpecial(const _UF actual,
             break;
 
         default:
-            break;
+            /*break // unreachable code */;
     }
 
     if (is_trait != should_be_trait)
@@ -938,7 +938,7 @@ void UnityAssertDoubleSpecial(const _UD actual,
             break;
 
         default:
-            break;
+            /*break // unreachable code*/;
     }
 
     if (is_trait != should_be_trait)