Tests: Fix pedantic warning about missing void in C function declaration

Tests/XCTest/StaticLibExample/StaticLibExample.c

@@ -1,6 +1,6 @@
 #include "StaticLibExample.h"
 
-int FourtyFour()
+int FourtyFour(void)
 {
   return 44;
 }

Tests/XCTest/StaticLibExample/StaticLibExample.h

@@ -1 +1 @@
-int FourtyFour();
+int FourtyFour(void);