Executor cannot find the aggr column in order-by clause if aggr column is not in the select clause.

[stonyw]

sqlglot==16.6.0

Related to #1822

('SELECT a, AVG(b) FROM x GROUP BY a ORDER BY AVG(b)', ["a", "_col_1"], [("b", 22.5), ("a", 25), ("c", 28)]), # PASS
('SELECT a FROM x GROUP BY a ORDER BY AVG(b)', ["a"], [("b",), ("a",), ("c",)]),  # FAILED

if avg not in select clause , i have the same issue.

Here is the error log.

Traceback (most recent call last):
  File "/Users/.../python3.11/site-packages/sqlglot/executor/python.py", line 46, in execute
    contexts[node] = self.sort(node, context)
                     ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/python.py", line 323, in sort
    sort_ctx.sort(self.generate_tuple(step.key))
  File "/Users/.../python3.11/site-packages/sqlglot/executor/context.py", line 81, in sort
    self.table.rows.sort(key=sort_key)
  File "/Users/.../python3.11/site-packages/sqlglot/executor/context.py", line 79, in sort_key
    return self.eval_tuple(key)
           ^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/context.py", line 38, in eval_tuple
    return tuple(self.eval(code) for code in codes)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/context.py", line 38, in <genexpr>
    return tuple(self.eval(code) for code in codes)
                 ^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/context.py", line 35, in eval
    return eval(code, self.env)
           ^^^^^^^^^^^^^^^^^^^^
  File "ORDERED(AVG(scope["x"]["b"]), False, True)", line 1, in <module>
  File "/Users/.../python3.11/site-packages/sqlglot/executor/table.py", line 104, in __getitem__
    return self.row[self.columns[column]]
                    ~~~~~~~~~~~~^^^^^^^^
KeyError: 'b'