update jme3-lwjgl3 to use LWJGL v3.3.4

[stephengold]

I don't want to delay JMonkeyEngine 3.7.0-stable, but at some point we should test with LWJGL v3.3.4 ...

https://github.com/LWJGL/lwjgl3/releases/tag/3.3.4

[stephengold]

The time has come. Self-assigning this issue.