Load infoschema operation in domain takes a long time

## Enhancement
Currently, when the load schema operation is executed on a cluster with hundreds of thousands of tables, the time and memory consumption are large. In particular, taking a long time can lead to some problems: https://github.com/pingcap/tidb/issues/45176

I tested the scenario myself:
```
Benchbot cluster, 1 TiDB, 3 TiKV, upgrade from v6.5.2 to v7.2.0
Make the first reload take 54s(create 500,000 tables ) in domain.Init for v7.2.0 branch.
```

At present, in addition to TiDB startup, the system information will be fully loaded, most of the other cases are incremental load table structure. But the problem still exists.