Bug: wrong binding for insert select

[chenzl25]

Describe the bug

create table t (a int);
create table t2 (b int);
insert into t select 1 as a from t2 group by a; -- Panic

explain insert into t select 1 as a from t2 group by a;
                                            QUERY PLAN
---------------------------------------------------------------------------------------------------
 BatchExchange { order: [], dist: Single }
 └─BatchInsert { table: t }
   └─BatchExchange { order: [], dist: Single }
     └─BatchProject { exprs: [1:Int32] }
       └─BatchHashAgg { group_key: [$expr1], aggs: [] }
         └─BatchExchange { order: [], dist: HashShard($expr1) }
           └─BatchProject { exprs: [CorrelatedInputRef { index: 0, correlated_id: 0 } as $expr1] }
             └─BatchScan { table: t2, columns: [] }

Error message/log

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To Reproduce

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Expected behavior

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How did you deploy RisingWave?

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The version of RisingWave

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Additional context

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