End gateway beams disappear when the end gateway block is not visible

The end gateway beam is culled when the source block isn't visible, similar to what used to happen with the beacon beam (MC-68247) although slightly less aggressive.

To reproduce

1. Run /setblock ~2 ~ ~ end_gateway to create an end gateway block.
2. Place a command block next to it.
3. Enter /data merge block ~1 ~ ~ {Age:100} into the command block.
4. Change the command block to a repeating, always-active command block.
5. The beam should now be visible.
6. Looking forward, fly up. After a few blocks, the beam should disappear.
7. When looking down, the beam will reappear.