[test]: add mock for test

[SamYuan1990]

should we consider using mock to increasing our test coverage?

[github-actions]

🤖 SeineSailor

Here is a concise summary of the pull request changes:

Summary: This pull request introduces mocking functionality for testing, updates the toolchain, and refactors test setup and teardown.

Key Modifications:

1. Mocking functionality: The go.uber.org/mock package (v0.5.0) is added, enabling mocking for testing purposes. Generated mocks for kubelet and cgroup packages improve test coverage and flexibility.
2. Toolchain update: The Go version is updated from 1.21.9 to 1.23.1.
3. Test setup and teardown refactoring: The BeforeSuite setup is removed, potentially affecting test behavior.

Impact on Codebase:

• Improved test coverage and flexibility with mocking functionality
• Updated toolchain may introduce compatibility changes
• Refactored test setup and teardown may require adjustments to test code

Suggestions for Improvement:

• Ensure thorough testing of the updated code to catch any compatibility issues
• Review and update existing test code to leverage the new mocking functionality
• Consider adding documentation or comments to explain the reasoning behind the test setup and teardown changes