### Godot version

4.0.beta16

### System information

Windows 10 Pro x64, GLES3, RTX 3080 Ti (528.02)

### Issue description

In Compatibility/GLES3 back-end, shaders which use a uniform to get the normal roughness buffer cannot compile. For example, the shader:
```glsl
shader_type spatial;

uniform sampler2D normal_roughness_texture : hint_normal_roughness_texture;

void fragment() {
    vec4 sample = texture(normal_roughness_texture, UV);
}
```
results in an error in the output:
```
  drivers/gles3/shader_gles3.cpp:242 - SceneShaderGLES3: Fragment shader compilation failed:
  0(890) : error C1503: undefined variable "normal_roughness_buffer"
  
  drivers/gles3/shader_gles3.cpp:342 - Method/function failed.
```

If I switch over to the Mobile or Forward+ backends, there is no shader compilation error.

### Steps to reproduce

Open the attached reproduction in the 4.0.beta16 editor.

When the scene is opened, the error is produced automatically:
1. Open `scene.tscn`
2. Open Output to review error

When the scene is saved with any changes made to the shader, the same error is also produced:
1. Open `scene.tscn`
2. Open `example.gdshader` in the shader editor.
3. Make a compile-able change to the shader.
4. Save the scene
5. Open Output to review the error

### Minimal reproduction project

[NormalRoughnessTexture_GLES3_Error.zip](https://github.com/godotengine/godot/files/10534253/NormalRoughnessTexture_GLES3_Error.zip)

{ TK_PRECISION_MID, "mediump", CF_BLOCK | CF_PRECISION_MODIFIER, {}, {} },
	{ TK_PRECISION_HIGH, "highp", CF_BLOCK | CF_PRECISION_MODIFIER, {}, {} },
	
	{ TK_UNIFORM, "uniform", CF_GLOBAL_SPACE | CF_UNIFORM_KEYWORD, {}, {} },
	{ TK_UNIFORM_GROUP, "group_uniforms", CF_GLOBAL_SPACE, {}, {} },
	{ TK_VARYING, "varying", CF_GLOBAL_SPACE, { "particles", "sky", "fog" }, {} },
	{ TK_CONST, "const", CF_BLOCK | CF_GLOBAL_SPACE | CF_CONST_KEYWORD, {}, {} },
	{ TK_STRUCT, "struct", CF_GLOBAL_SPACE, {}, {} },
	{ TK_SHADER_TYPE, "shader_type", CF_SHADER_TYPE, {}, {} },
	{ TK_RENDER_MODE, "render_mode", CF_GLOBAL_SPACE, {}, {} },
	
	{ TK_INSTANCE, "instance", CF_GLOBAL_SPACE | CF_UNIFORM_QUALIFIER, {}, {} },
	{ TK_GLOBAL, "global", CF_GLOBAL_SPACE | CF_UNIFORM_QUALIFIER, {}, {} },
	
	{ TK_CF_IF, "if", CF_BLOCK, {}, {} },
	{ TK_CF_ELSE, "else", CF_BLOCK, {}, {} },
	{ TK_CF_FOR, "for", CF_BLOCK, {}, {} },
	{ TK_CF_WHILE, "while", CF_BLOCK, {}, {} },
	{ TK_CF_DO, "do", CF_BLOCK, {}, {} },
	{ TK_CF_SWITCH, "switch", CF_BLOCK, {}, {} },
	{ TK_CF_CASE, "case", CF_BLOCK, {}, {} },
	{ TK_CF_DEFAULT, "default", CF_BLOCK, {}, {} },
	{ TK_CF_BREAK, "break", CF_BLOCK, {}, {} },
	{ TK_CF_CONTINUE, "continue", CF_BLOCK, {}, {} },
	{ TK_CF_RETURN, "return", CF_BLOCK, {}, {} },
	{ TK_CF_DISCARD, "discard", CF_BLOCK, { "particles", "sky", "fog" }, { "fragment" } },
	
	{ TK_ARG_IN, "in", CF_FUNC_DECL_PARAM_SPEC, {}, {} },
	{ TK_ARG_OUT, "out", CF_FUNC_DECL_PARAM_SPEC, {}, {} },
	{ TK_ARG_INOUT, "inout", CF_FUNC_DECL_PARAM_SPEC, {}, {} },