### 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)

OperatorNode *func = alloc_node<OperatorNode>();
				func->op = OP_EMPTY;
				expr = func;
			}
			if (!valid) {
				if (tk.type != TK_SEMICOLON) {
					_set_error(vformat(RTR("Expected expression, found: '%s'."), get_token_text(tk)));
					return nullptr;
				} else {
#ifdef DEBUG_ENABLED
					if (!p_block || (p_block->block_type != BlockNode::BLOCK_TYPE_FOR_INIT && p_block->block_type != BlockNode::BLOCK_TYPE_FOR_CONDITION)) {
						if (check_warnings && HAS_WARNING(ShaderWarning::FORMATTING_ERROR_FLAG)) {
							_add_line_warning(ShaderWarning::FORMATTING_ERROR, RTR("Empty statement. Remove ';' to fix this warning."));
						}
					}
#endif 
					_set_tkpos(prepos);
					OperatorNode *func = alloc_node<OperatorNode>();
					func->op = OP_EMPTY;
					expr = func;
				}
			}
		}
		ERR_FAIL_COND_V(!expr, nullptr);
		
		while (true) {
			TkPos pos2 = _get_tkpos();
			tk = _get_token();
			if (tk.type == TK_CURSOR) {