Fix __traits(getFunctionAttributes) example

The example code runner wraps the code in a function if no `main`
is found, which makes the functions nested and changes attribute
inference. Also the printed message is `tuple(...)` instead of `(...)`.

Author: n8sh

spec/traits.dd

@@ -735,26 +735,41 @@ $(SPEC_RUNNABLE_EXAMPLE_COMPILE
 ---
 int sum(int x, int y) pure nothrow { return x + y; }
 
-// prints ("pure", "nothrow", "@system")
 pragma(msg, __traits(getFunctionAttributes, sum));
 
 struct S
 {
     void test() const @system { }
 }
 
-// prints ("const", "@system")
 pragma(msg, __traits(getFunctionAttributes, S.test));
+
+void main(){}
 ---
+)
+
+        Prints:
+
+$(CONSOLE
+tuple("pure", "nothrow", "@system")
+tuple("const", "@system")
 )
 
     $(P Note that some attributes can be inferred. For example:)
 
 $(SPEC_RUNNABLE_EXAMPLE_COMPILE
 ---
-// prints ("pure", "nothrow", "@nogc", "@trusted")
 pragma(msg, __traits(getFunctionAttributes, (int x) @trusted { return x * 2; }));
+
+void main(){}
 ---
+)
+
+        Prints:
+
+$(CONSOLE
+tuple("pure", "nothrow", "@nogc", "@trusted")
+)
 )
 )