found unexpected goroutines github.com/tikv/client-go/v2/config/retry.(*Config).createBackoffFn.newBackoffFn.func2

[lance6716]

goleak: Errors on successful test run: found unexpected goroutines:

[Goroutine 119983 in state select, with github.com/tikv/client-go/v2/config/retry.(*Config).createBackoffFn.newBackoffFn.func2 on top of the stack:

github.com/tikv/client-go/v2/config/retry.(*Config).createBackoffFn.newBackoffFn.func2({0x97b7b68, 0xd881bc0}, 0xffffffffffffffff)

	external/com_github_tikv_client_go_v2/config/retry/config.go:194 +0x5f5

github.com/tikv/client-go/v2/config/retry.(*Backoffer).BackoffWithCfgAndMaxSleep(0xc01cc58d80, 0xc000c4f9e0, 0x18?, {0x9787700, 0xc03436d8c0})

	external/com_github_tikv_client_go_v2/config/retry/backoff.go:195 +0xb44

github.com/tikv/client-go/v2/config/retry.(*Backoffer).Backoff(0xc01cc58d80, 0xc000c4f9e0, {0x9787700, 0xc03436d8c0})

	external/com_github_tikv_client_go_v2/config/retry/backoff.go:122 +0x2d5

github.com/tikv/client-go/v2/tikv.(*KVStore).getTimestampWithRetry(0xc00083f800, 0xc01cc58d80, {0x7c95987, 0x6})

	external/com_github_tikv_client_go_v2/tikv/kv.go:435 +0x5fd

github.com/tikv/client-go/v2/tikv.(*KVStore).GetTimestampWithRetry(0xc002df1ba0?, 0xc002df19f8?, {0x7c95987, 0x6})

	external/com_github_tikv_client_go_v2/tikv/kv.go:410 +0x45

github.com/tikv/client-go/v2/txnkv/transaction.keepAlive(0xc00ab61880, 0xc00266c9c0, {0xc004183024, 0x13, 0x13}, 0xc0255bc8c0)

	external/com_github_tikv_client_go_v2/txnkv/transaction/2pc.go:1170 +0x612

created by github.com/tikv/client-go/v2/txnkv/transaction.(*ttlManager).run in goroutine 117003

	external/com_github_tikv_client_go_v2/txnkv/transaction/2pc.go:1130 +0x2e6

]

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