### 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)

} else if (na == TYPE_VEC4 && nb == TYPE_FLOAT) {
				valid = true;
				ret_type = TYPE_VEC4;
			} else if (na == TYPE_MAT2 && nb == TYPE_FLOAT) {
				valid = true;
				ret_type = TYPE_MAT2;
			} else if (na == TYPE_MAT3 && nb == TYPE_FLOAT) {
				valid = true;
				ret_type = TYPE_MAT3;
			} else if (na == TYPE_MAT4 && nb == TYPE_FLOAT) {
				valid = true;
				ret_type = TYPE_MAT4;
			} else if (p_op->op == OP_ASSIGN_MUL && na == TYPE_VEC2 && nb == TYPE_MAT2) {
				valid = true;
				ret_type = TYPE_VEC2;
			} else if (p_op->op == OP_ASSIGN_MUL && na == TYPE_VEC3 && nb == TYPE_MAT3) {
				valid = true;
				ret_type = TYPE_VEC3;
			} else if (p_op->op == OP_ASSIGN_MUL && na == TYPE_VEC4 && nb == TYPE_MAT4) {
				valid = true;
				ret_type = TYPE_VEC4;
			}
		} break;
		case OP_ASSIGN_BIT_AND:
		case OP_ASSIGN_BIT_OR:
		case OP_ASSIGN_BIT_XOR:
		case OP_BIT_AND:
		case OP_BIT_OR:
		case OP_BIT_XOR: {
			/*