GPULightmapper: increase ray triangle hit rate
GPULightmapper: increase ray triangle hit rate

Currently the method ray_hits_triangle determines triangles not to be hit by
a ray due to an epsilon that is too big. In practice those triangles are hit by
those rays.

This is fixed by introducing a smaller epsilon.

Shockblast/godot,Faless/godot,Faless/godot,josempans/godot,Faless/godot,vkbsb/godot,Zylann/godot,firefly2442/godot,vnen/godot,Valentactive/godot,ZuBsPaCe/godot,godotengine/godot,firefly2442/godot,akien-mga/godot,ZuBsPaCe/godot,Shockblast/godot,josempans/godot,Zylann/godot,vnen/godot,firefly2442/godot,godotengine/godot,firefly2442/godot,josempans/godot,Valentactive/godot,josempans/godot,ZuBsPaCe/godot,vnen/godot,firefly2442/godot,BastiaanOlij/godot,vkbsb/godot,sanikoyes/godot,guilhermefelipecgs/godot,josempans/godot,sanikoyes/godot,Shockblast/godot,Shockblast/godot,Shockblast/godot,godotengine/godot,vkbsb/godot,guilhermefelipecgs/godot,vnen/godot,BastiaanOlij/godot,pkowal1982/godot,godotengine/godot,vkbsb/godot,BastiaanOlij/godot,BastiaanOlij/godot,Valentactive/godot,sanikoyes/godot,akien-mga/godot,pkowal1982/godot,vnen/godot,Zylann/godot,ZuBsPaCe/godot,josempans/godot,godotengine/godot,guilhermefelipecgs/godot,godotengine/godot,BastiaanOlij/godot,akien-mga/godot,guilhermefelipecgs/godot,Shockblast/godot,Zylann/godot,guilhermefelipecgs/godot,Zylann/godot,Zylann/godot,Valentactive/godot,vkbsb/godot,Valentactive/godot,firefly2442/godot,pkowal1982/godot,ZuBsPaCe/godot,ZuBsPaCe/godot,guilhermefelipecgs/godot,godotengine/godot,ZuBsPaCe/godot,akien-mga/godot,ZuBsPaCe/godot,Faless/godot,Zylann/godot,Shockblast/godot,Faless/godot,Valentactive/godot,Valentactive/godot,Faless/godot,godotengine/godot,pkowal1982/godot,Faless/godot,josempans/godot,sanikoyes/godot,pkowal1982/godot,vkbsb/godot,Zylann/godot,pkowal1982/godot,akien-mga/godot,pkowal1982/godot,akien-mga/godot,guilhermefelipecgs/godot,sanikoyes/godot,akien-mga/godot,BastiaanOlij/godot,vnen/godot,sanikoyes/godot,BastiaanOlij/godot,pkowal1982/godot,vkbsb/godot,Valentactive/godot,firefly2442/godot,josempans/godot,sanikoyes/godot,sanikoyes/godot,akien-mga/godot,BastiaanOlij/godot,Shockblast/godot,Faless/godot,vnen/godot,vnen/godot,firefly2442/godot,guilhermefelipecgs/godot,vkbsb/godot