Regression from #71248:

I believe this pull may have caused errors on WebGL since it moves the `GLES_OVER_GL` guard. WebGL does not support texture swizzling per: https://registry.khronos.org/webgl/specs/latest/2.0/#5.19
so this is causing the following trace in Chrome:
```
WebGL: INVALID_ENUM: texParameter: invalid parameter name
```
and it quickly fills up the 256 log limit for the same message in WebGL.

This doesn't appear to be breaking anything asides from causing the numerous log messages.

_Originally posted by @jnlopar in https://github.com/godotengine/godot/issues/71248#issuecomment-1384768973_

CC @rsjtdrjgfuzkfg @clayjohn
return singleton;
}
static const GLenum _cube_side_enum[6] = {
	GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
	GL_TEXTURE_CUBE_MAP_POSITIVE_X,
	GL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
	GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
	GL_TEXTURE_CUBE_MAP_NEGATIVE_Z,
	GL_TEXTURE_CUBE_MAP_POSITIVE_Z,
};
TextureStorage::TextureStorage() {
	singleton = this;
	system_fbo = 0;
	{ 
		{ 
			Ref<Image> image = Image::create_empty(4, 4, true, Image::FORMAT_RGBA8);
			image->fill(Color(1, 1, 1, 1));
			image->generate_mipmaps();
			default_gl_textures[DEFAULT_GL_TEXTURE_WHITE] = texture_allocate();
			texture_2d_initialize(default_gl_textures[DEFAULT_GL_TEXTURE_WHITE], image);
			Vector<Ref<Image>> images;
			images.push_back(image);
			default_gl_textures[DEFAULT_GL_TEXTURE_2D_ARRAY_WHITE] = texture_allocate();
			texture_2d_layered_initialize(default_gl_textures[DEFAULT_GL_TEXTURE_2D_ARRAY_WHITE], images, RS::TEXTURE_LAYERED_2D_ARRAY);
			for (int i = 0; i < 3; i++) {
				images.push_back(image);
			}
			default_gl_textures[DEFAULT_GL_TEXTURE_3D_WHITE] = texture_allocate();
			texture_3d_initialize(default_gl_textures[DEFAULT_GL_TEXTURE_3D_WHITE], image->get_format(), 4, 4, 4, false, images);
			for (int i = 0; i < 2; i++) {