fix camera plot for new matplotlib

Summary: fixes https://github.com/facebookresearch/pytorch3d/issues/1554 , needed for Matplotlib 3.6+

Reviewed By: patricklabatut

Differential Revision: D46438822

fbshipit-source-id: f3c06ad5d8e881a635edd14f96d498dca73c169f

docs/tutorials/utils/camera_visualization.py

@@ -33,7 +33,7 @@ def plot_camera_scene(cameras, cameras_gt, status: str):
     a string passed inside the `status` argument.
     """
     fig = plt.figure()
-    ax = fig.gca(projection="3d")
+    ax = fig.add_subplot(projection="3d")
     ax.clear()
     ax.set_title(status)
     handle_cam = plot_cameras(ax, cameras, color="#FF7D1E")