Add cull and lightmap probe influence benchmarks

[OverloadedOrama]

Adds the following benchmarks from #36:

• 🟥CPU🟥 [Cull]: Rotating: Cull 10k rotating objects
• 🟥CPU🟥 [Cull Omni Shadows]: Static: Cull 10k objects, 200 omni lights with shadows, static
• 🟥CPU🟥 [Cull Spot Shadows]: Static: Cull 10k objects, 200 omni lights with shadows, static
• 🟥CPU🟥 [Cull Spot Shadows]: Dynamic: Cull 10k objects, 200 omni lights with shadows, lights move around.
• 🟥CPU🟥 Lightmap probe influence : Simple scene baked with lightmaps (and using tons of probes, like 500), 1000 objects moving around receiving influence from probes.

The rest of the CPU benchmarks under 3D rendering seem to be already implemented in culling.gd

I also formatted culling.gd and improved its static typing.

Results on my PC

{
"benchmarks": [
{
"category": "Rendering > Culling",
"name": "Dynamic Rotate Cull",
"results": {
"render_cpu": 6.082,
"render_gpu": 2.836,
"time": 2.812
}
},
{
"category": "Rendering > Culling",
"name": "Dynamic Spot Light Cull With Shadows",
"results": {
"render_cpu": 2.44,
"render_gpu": 3.092,
"time": 3.426
}
},
{
"category": "Rendering > Culling",
"name": "Static Omni Light Cull With Shadows",
"results": {
"render_cpu": 1.365,
"render_gpu": 3.043,
"time": 0.047
}
},
{
"category": "Rendering > Culling",
"name": "Static Spot Light Cull With Shadows",
"results": {
"render_cpu": 1.585,
"render_gpu": 3.063,
"time": 0.065
}
},
{
"category": "Rendering > Lightmap Probe Influence",
"name": "Lightmap Probe Influence",
"results": {
"render_cpu": 0.9369,
"render_gpu": 3.131,
"time": 10.8
}
}
],
"engine": {
"version": "v4.3.beta1.official",
"version_hash": "a4f2ea91a1bd18f70a43ff4c1377db49b56bc3f0"
},
"system": {
"cpu_architecture": "x86_64",
"cpu_count": 12,
"cpu_name": "AMD Ryzen 5 1600 Six-Core Processor",
"os": "Linux"
}
}

[Calinou]

Tested locally, it works as expected.

Note that I've amended the Lightmap Probe Influence benchmark in 74ed0f7 (#74) (see commit message for reasons), so that the probe influence can actually be seen on the moving objects.

Thanks!