### 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)

flow->flow_op = FLOW_OP_CONTINUE;
			pos = _get_tkpos();
			tk = _get_token();
			if (tk.type != TK_SEMICOLON) {
				
				_set_expected_after_error(";", "continue");
				return ERR_PARSE_ERROR;
			}
			p_block->statements.push_back(flow);
		} else {
			
			_set_tkpos(pos); 
			Node *expr = _parse_and_reduce_expression(p_block, p_function_info);
			if (!expr) {
				return ERR_PARSE_ERROR;
			}
			is_condition = expr->type == Node::TYPE_OPERATOR && expr->get_datatype() == TYPE_BOOL;
			if (expr->type == Node::TYPE_OPERATOR) {
				OperatorNode *op = static_cast<OperatorNode *>(expr);
				if (op->op == OP_EMPTY) {
					is_var_init = true;
					is_condition = true;
				}
			}
			p_block->statements.push_back(expr);
			tk = _get_token();
			if (p_block->block_type == BlockNode::BLOCK_TYPE_FOR_CONDITION) {
				if (tk.type == TK_COMMA) {
					if (!is_condition) {
						_set_error(RTR("The middle expression is expected to be a boolean operator."));