copIteratorWork meet panic: runtime error: index out of range [736] with length 72

## Bug Report

Please answer these questions before submitting your issue. Thanks!

### 1. Minimal reproduce step (Required)

### 2. What did you expect to see? (Required)
no panic

### 3. What did you see instead (Required)
```
2024-09-14 11:12:13 (UTC+08:00)TiDB 10.20.20.138:4001[coprocessor.go:1161] ["copIteratorWork meet panic"] [r="runtime error: index out of range [736] with length 728"]
["stack trace"="github.com/pingcap/tidb/pkg/store/copr.(*copIteratorWorker).handleTask.func1
/workspace/source/tidb/pkg/store/copr/coprocessor.go:1163
runtime.gopanic
/usr/local/go/src/runtime/panic.go:914
runtime.goPanicIndex
/usr/local/go/src/runtime/panic.go:114
github.com/pingcap/tidb/pkg/store/copr.coprCacheBuildKey
/workspace/source/tidb/pkg/store/copr/coprocessor_cache.go:157
github.com/pingcap/tidb/pkg/store/copr.(*copIteratorWorker).buildCacheKey
/workspace/source/tidb/pkg/store/copr/coprocessor.go:1704
github.com/pingcap/tidb/pkg/store/copr.(*copIteratorWorker).handleTaskOnce
/workspace/source/tidb/pkg/store/copr/coprocessor.go:1216
github.com/pingcap/tidb/pkg/store/copr.(*copIteratorWorker).handleTask
/workspace/source/tidb/pkg/store/copr/coprocessor.go:1174
github.com/pingcap/tidb/pkg/store/copr.(*copIteratorWorker).run
/workspace/source/tidb/pkg/store/copr/coprocessor.go:836"]

```

### 4. What is your TiDB version? (Required)

v8.1.0