app/gfx: add missing ctx.end_render_pass() call at the end of the gfx draw() method.

bin/app/src/gfx/mod.rs

@@ -1711,6 +1711,7 @@ impl EventHandler for Stage {
         };
         render_ctx.draw();
 
+        self.ctx.end_render_pass();
         self.ctx.commit_frame();
     }