Optimize the lock usage in resource controller

## Development Task

```
79574260 2380 @ 0x1037b3079 0x1037b305a 0x1037ad6c5 0x1037cc578 0x1037cbee2 0x1037d1c73 0x1037cb31d 0x1037d16d3 0x1037fa592 0x1037f6c7b 0x10385bded 0x103863632 0x1038624c5 0x10464bbcb 0x10626b9bb 0x10626ab8b 0x1062693f2 0x1057e251f 0x106126fae 0x10611e828 0x10643f662 0x1064aeb4c 0x1064adfd3 0x1064b3727 0x1064b2b30 0x1064b26a9 0x1064a70bb 0x1064a3288 0x1064c6adf 0x1064c5425 0x102b717a1
# 0x1037b3078 sync.(*Mutex).Unlock+0x1b8 /Users/siddon/go/pkg/mod/[golang.org/toolchain@v0.0.1-go1.23.4.darwin-amd64/src/sync/mutex.go:225](http://golang.org/toolchain@v0.0.1-go1.23.4.darwin-amd64/src/sync/mutex.go:225)
# 0x1037b3059 [github.com/tikv/pd/client/resource_group/controller.(*groupCostController).onRequestWaitImpl+0x199](http://github.com/tikv/pd/client/resource_group/controller.(*groupCostController).onRequestWaitImpl+0x199) /Users/siddon/go/pkg/mod/[github.com/tikv/pd/client@v0.0.0-20241111073742-238d4d79ea31/resource_group/controller/controller.go:1400](http://github.com/tikv/pd/client@v0.0.0-20241111073742-238d4d79ea31/resource_group/controller/controller.go:1400)
# 0x1037ad6c4 [github.com/tikv/pd/client/resource_group/controller.(*ResourceGroupsController).OnRequestWait+0x64](http://github.com/tikv/pd/client/resource_group/controller.(*ResourceGroupsController).OnRequestWait+0x64) /Users/siddon/go/pkg/mod/[github.com/tikv/pd/client@v0.0.0-20241111073742-238d4d79ea31/resource_group/controller/controller.go:646](http://github.com/tikv/pd/client@v0.0.0-20241111073742-238d4d79ea31/resource_group/controller/controller.go:646)
# 0x1037cc577 [github.com/tikv/client-go/v2/internal/client.buildResourceControlInterceptor.func1.1+0x137](http://github.com/tikv/client-go/v2/internal/client.buildResourceControlInterceptor.func1.1+0x137) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/client/client_interceptor.go:108](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/client/client_interceptor.go:108)
# 0x1037cbee1 [github.com/tikv/client-go/v2/internal/client.interceptedClient.SendRequest+0x1c1](http://github.com/tikv/client-go/v2/internal/client.interceptedClient.SendRequest+0x1c1) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/client/client_interceptor.go:58](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/client/client_interceptor.go:58)
# 0x1037d1c72 [github.com/tikv/client-go/v2/internal/client.(*interceptedClient).SendRequest+0x52](http://github.com/tikv/client-go/v2/internal/client.(*interceptedClient).SendRequest+0x52) :1
# 0x1037cb31c [github.com/tikv/client-go/v2/internal/client.reqCollapse.SendRequest+0xbc](http://github.com/tikv/client-go/v2/internal/client.reqCollapse.SendRequest+0xbc) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/client/client_collapse.go:74](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/client/client_collapse.go:74)
# 0x1037d16d2 [github.com/tikv/client-go/v2/internal/client.(*reqCollapse).SendRequest+0x52](http://github.com/tikv/client-go/v2/internal/client.(*reqCollapse).SendRequest+0x52) :1
# 0x1037fa591 [github.com/tikv/client-go/v2/internal/locate.(*RegionRequestSender).sendReqToRegion+0x8d1](http://github.com/tikv/client-go/v2/internal/locate.(*RegionRequestSender).sendReqToRegion+0x8d1) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/locate/region_request.go:1114](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/locate/region_request.go:1114)
# 0x1037f6c7a [github.com/tikv/client-go/v2/internal/locate.(*RegionRequestSender).SendReqCtx+0x14ba](http://github.com/tikv/client-go/v2/internal/locate.(*RegionRequestSender).SendReqCtx+0x14ba) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/locate/region_request.go:870](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/internal/locate/region_request.go:870)
# 0x10385bdec [github.com/tikv/client-go/v2/txnkv/txnsnapshot.(*ClientHelper).SendReqCtx+0x22c](http://github.com/tikv/client-go/v2/txnkv/txnsnapshot.(*ClientHelper).SendReqCtx+0x22c) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/txnkv/txnsnapshot/client_helper.go:146](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/txnkv/txnsnapshot/client_helper.go:146)
# 0x103863631 [github.com/tikv/client-go/v2/txnkv/txnsnapshot.(*KVSnapshot).get+0xb71](http://github.com/tikv/client-go/v2/txnkv/txnsnapshot.(*KVSnapshot).get+0xb71) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/txnkv/txnsnapshot/snapshot.go:721](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/txnkv/txnsnapshot/snapshot.go:721)
# 0x1038624c4 [github.com/tikv/client-go/v2/txnkv/txnsnapshot.(*KVSnapshot).Get+0x5c4](http://github.com/tikv/client-go/v2/txnkv/txnsnapshot.(*KVSnapshot).Get+0x5c4) /Users/siddon/go/pkg/mod/[github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/txnkv/txnsnapshot/snapshot.go:633](http://github.com/tikv/client-go/v2@v2.0.8-0.20241120024459-05d115b3e88b/txnkv/txnsnapshot/snapshot.go:633)
# 0x10464bbca [github.com/pingcap/tidb/pkg/store/driver/txn.(*tikvSnapshot).Get+0xea](http://github.com/pingcap/tidb/pkg/store/driver/txn.(*tikvSnapshot).Get+0xea) /Users/siddon/eng/tidb/pkg/store/driver/txn/snapshot.go:60
# 0x10626b9ba [github.com/pingcap/tidb/pkg/executor.(*PointGetExecutor).get+0x4da](http://github.com/pingcap/tidb/pkg/executor.(*PointGetExecutor).get+0x4da) /Users/siddon/eng/tidb/pkg/executor/point_get.go:687
# 0x10626ab8a [github.com/pingcap/tidb/pkg/executor.(*PointGetExecutor).getAndLock+0x18a](http://github.com/pingcap/tidb/pkg/executor.(*PointGetExecutor).getAndLock+0x18a) /Users/siddon/eng/tidb/pkg/executor/point_get.go:561
# 0x1062693f1 [github.com/pingcap/tidb/pkg/executor.(*PointGetExecutor).Next+0x771](http://github.com/pingcap/tidb/pkg/executor.(*PointGetExecutor).Next+0x771) /Users/siddon/eng/tidb/pkg/executor/point_get.go:394

```
there are too many locks.