Fix GLES2 automatic texture lookup in canvas
Fix GLES2 automatic texture lookup in canvas

After this change the color will only be fetched if the shader code doesn't use it explicitly, to match the GLES3 behaviour.

Fixes #23179.

ex/godot,firefly2442/godot,MarianoGnu/godot,godotengine/godot,honix/godot,guilhermefelipecgs/godot,BastiaanOlij/godot,pkowal1982/godot,mcanders/godot,honix/godot,ZuBsPaCe/godot,okamstudio/godot,godotengine/godot,Paulloz/godot,Paulloz/godot,DmitriySalnikov/godot,BastiaanOlij/godot,akien-mga/godot,guilhermefelipecgs/godot,sanikoyes/godot,firefly2442/godot,vkbsb/godot,Shockblast/godot,groud/godot,sanikoyes/godot,Faless/godot,vkbsb/godot,Shockblast/godot,okamstudio/godot,Valentactive/godot,Faless/godot,ZuBsPaCe/godot,godotengine/godot,okamstudio/godot,vkbsb/godot,Shockblast/godot,Faless/godot,Paulloz/godot,Faless/godot,Valentactive/godot,Valentactive/godot,ex/godot,MarianoGnu/godot,Zylann/godot,sanikoyes/godot,vnen/godot,pkowal1982/godot,josempans/godot,Valentactive/godot,BastiaanOlij/godot,sanikoyes/godot,BastiaanOlij/godot,Zylann/godot,akien-mga/godot,okamstudio/godot,MarianoGnu/godot,Paulloz/godot,vnen/godot,MarianoGnu/godot,Shockblast/godot,firefly2442/godot,ZuBsPaCe/godot,sanikoyes/godot,ex/godot,Valentactive/godot,akien-mga/godot,guilhermefelipecgs/godot,BastiaanOlij/godot,okamstudio/godot,okamstudio/godot,ZuBsPaCe/godot,akien-mga/godot,ZuBsPaCe/godot,pkowal1982/godot,guilhermefelipecgs/godot,firefly2442/godot,DmitriySalnikov/godot,DmitriySalnikov/godot,MarianoGnu/godot,godotengine/godot,sanikoyes/godot,ex/godot,okamstudio/godot,Shockblast/godot,Paulloz/godot,ex/godot,guilhermefelipecgs/godot,akien-mga/godot,akien-mga/godot,vkbsb/godot,Paulloz/godot,BastiaanOlij/godot,pkowal1982/godot,firefly2442/godot,josempans/godot,guilhermefelipecgs/godot,Zylann/godot,pkowal1982/godot,vkbsb/godot,honix/godot,Valentactive/godot,vnen/godot,ex/godot,vnen/godot,josempans/godot,guilhermefelipecgs/godot,mcanders/godot,okamstudio/godot,Paulloz/godot,MarianoGnu/godot,josempans/godot,vnen/godot,Shockblast/godot,ZuBsPaCe/godot,vnen/godot,ZuBsPaCe/godot,pkowal1982/godot,Faless/godot,honix/godot,honix/godot,godotengine/godot,Faless/godot,Zylann/godot,godotengine/godot,Faless/godot,josempans/godot,josempans/godot,BastiaanOlij/godot,DmitriySalnikov/godot,MarianoGnu/godot,vkbsb/godot,DmitriySalnikov/godot,MarianoGnu/godot,guilhermefelipecgs/godot,honix/godot,firefly2442/godot,vnen/godot,DmitriySalnikov/godot,firefly2442/godot,akien-mga/godot,BastiaanOlij/godot,godotengine/godot,vnen/godot,sanikoyes/godot,groud/godot,okamstudio/godot,mcanders/godot,Zylann/godot,Shockblast/godot,Zylann/godot,vkbsb/godot,mcanders/godot,vkbsb/godot,Zylann/godot,pkowal1982/godot,mcanders/godot,Shockblast/godot,ZuBsPaCe/godot,Zylann/godot,groud/godot,mcanders/godot,okamstudio/godot,ex/godot,groud/godot,josempans/godot,Valentactive/godot,ex/godot,Faless/godot,groud/godot,pkowal1982/godot,sanikoyes/godot,firefly2442/godot,groud/godot,akien-mga/godot,Valentactive/godot,DmitriySalnikov/godot,godotengine/godot,josempans/godot