[libcalamares] Fix build with GCC

- <memory> isn't implicitly-included for std::unique_ptr

src/libcalamares/PythonJob.h

@@ -21,11 +21,12 @@
 #define CALAMARES_PYTHONJOB_H
 
 #include "Job.h"
-
 #include "modulesystem/InstanceKey.h"
 
 #include <QVariantMap>
 
+#include <memory>
+
 namespace CalamaresPython
 {
 class PythonJobInterface;