rewritten one of the shader load functions

OpenGL/cube/src/main.cpp

@@ -121,6 +121,7 @@ int main(int argc, char** argv) {
     }
 
 	game->isWindowClosed = true;
+    ~simpleShader()
     SDL_GL_DeleteContext(game->glContext);
 	SDL_DestroyWindow(game->window);
 	SDL_Quit();