Use %% for actual % in spec

rpmlint reports this as macro in comment, however it was left here, because it
is not macro and not comment. On the other hand, % shall be escaped using %%.
All this needs to blow is somebody defining a macro called _pyconfig64_h.

python37.spec

@@ -853,9 +853,9 @@ InstallPython() {
 #include <bits/wordsize.h>
 
 #if __WORDSIZE == 32
-#include "%{_pyconfig32_h}"
+#include "%%{_pyconfig32_h}"
 #elif __WORDSIZE == 64
-#include "%{_pyconfig64_h}"
+#include "%%{_pyconfig64_h}"
 #else
 #error "Unknown word size"
 #endif