refactor: use t.TempDir() instead of os.MkdirTemp

[tgolang]

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Close #XXX

TempDir() is a method introduced in Go 1.15 for testing.T. It automatically creates a temporary directory and cleans it up after the test is complete, eliminating the hassle of manually handling errors and cleanup. More detail about TempDir https://pkg.go.dev/testing#B.TempDir

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[mtsitrin]

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[tgolang]

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