Add @deprecated to RGBFormat (#24426)

* Update constants.js

* Update constants.js

Co-authored-by: Michael Herzog <[email protected]>

src/constants.js

@@ -85,7 +85,7 @@ export const UnsignedShort4444Type = 1017;
 export const UnsignedShort5551Type = 1018;
 export const UnsignedInt248Type = 1020;
 export const AlphaFormat = 1021;
-export const RGBFormat = 1022;
+export const RGBFormat = 1022; // @deprecated since r137
 export const RGBAFormat = 1023;
 export const LuminanceFormat = 1024;
 export const LuminanceAlphaFormat = 1025;