### Godot version

v4.0.beta13.official [caacade56]

### System information

Windows 8.1

### Issue description

The `Unreachable code (statement after return) in function 'function_name()'` warning is given for functions that do not have unreachable code. The same code does not give this warning in v3.5.stable.official [991bb6ac7].

### Steps to reproduce

```
func warning(i: int) -> void:
  if i == 0:
    pass
  elif i == 1:
    return
  else:
    return
  print("yeah")
```

Removing either the `elif` or the `else` removes the warning.

### Minimal reproduction project

N/A; code in reproduction steps can be placed in any blank gdscript file to trigger the error.
assignment->assignee = p_previous_operand;
	assignment->assigned_value = parse_expression(false);
	if (assignment->assigned_value == nullptr) {
		push_error(R"(Expected an expression after "=".)");
	}
	complete_extents(assignment);
#ifdef DEBUG_ENABLED
	if (source_variable != nullptr) {
		if (has_operator && source_variable->assignments == 0) {
			push_warning(assignment, GDScriptWarning::UNASSIGNED_VARIABLE_OP_ASSIGN, source_variable->identifier->name);
		}
		source_variable->assignments += 1;
	}
#endif
	return assignment;
}
GDScriptParser::ExpressionNode *GDScriptParser::parse_await(ExpressionNode *p_previous_operand, bool p_can_assign) {
	AwaitNode *await = alloc_node<AwaitNode>();
	ExpressionNode *element = parse_precedence(PREC_AWAIT, false);
	if (element == nullptr) {
		push_error(R"(Expected signal or coroutine after "await".)");
	}
	await->to_await = element;
	complete_extents(await);
	if (current_function) { 
		current_function->is_coroutine = true;
	}
	return await;
}
GDScriptParser::ExpressionNode *GDScriptParser::parse_array(ExpressionNode *p_previous_operand, bool p_can_assign) {