test: Simplify the hello.c test app

test/hello.c

@@ -16,10 +16,9 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#define __USE_MINGW_ANSI_STDIO 1
 #include <stdio.h>
 
 int main(int argc, char* argv[]) {
-    printf("hello world! %f\n", 42.0);
+    printf("Hello world!\n");
     return 0;
 }