### 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)

for (int i = 0; i < call_function->arguments.size(); i++) {
								int argidx = i + 1;
								if (argidx < func->arguments.size()) {
									bool error = false;
									Node *n = func->arguments[argidx];
									ArgumentQualifier arg_qual = call_function->arguments[i].qualifier;
									bool is_out_arg = arg_qual != ArgumentQualifier::ARGUMENT_QUALIFIER_IN;
									if (n->type == Node::TYPE_VARIABLE || n->type == Node::TYPE_ARRAY) {
										StringName varname;
										if (n->type == Node::TYPE_VARIABLE) {
											VariableNode *vn = static_cast<VariableNode *>(n);
											varname = vn->name;
										} else { 
											ArrayNode *an = static_cast<ArrayNode *>(n);
											varname = an->name;
										}
										if (shader->varyings.has(varname)) {
											switch (shader->varyings[varname].stage) {
												case ShaderNode::Varying::STAGE_UNKNOWN: {
													_set_error(vformat(RTR("Varying '%s' must be assigned in the 'vertex' or 'fragment' function first."), varname));
													return nullptr;
												}
												case ShaderNode::Varying::STAGE_VERTEX_TO_FRAGMENT_LIGHT:
													[[fallthrough]];
												case ShaderNode::Varying::STAGE_VERTEX:
													if (is_out_arg && current_function != varying_function_names.vertex) { 
														error = true;
													}
													break;
												case ShaderNode::Varying::STAGE_FRAGMENT_TO_LIGHT: