test: replace gomonkey with xgo

[xhd2015]

This PR changes test cases that use gomonkey, replacing that with xgo.

The xgo, which is a native-go solution of monkey patching, have the following advantages compared to gomonkey:

• Compatibility
  • xgo provides support through go1.17 to go1.22, for all OS and Arch, while gomonkey has limited support
• Stability
  • xgo does not need to modify readonly area, so on MacOS developers does not need any extra setup
• Concurrent Safety
  • xgo has built-in concurrent safety, patchings are isolated among goroutines, tests do not affect each other. While gomonkey is not concurrently safe
• Simplicity
  • xgo provides a powerful API named Patch, which can smartly recognize the target to mock

With this introduction of xgo and removal of gomonkey, future tests can use xgo reliably.

The xgo project: https://github.com/xhd2015/xgo.

To run the tests, xgo needs to be installed:

# macOS and Linux (and WSL)
curl -fsSL https://github.com/xhd2015/xgo/raw/master/install.sh | bash

# windows
powershell -c "irm github.com/xhd2015/xgo/raw/master/install.ps1|iex"

Then run:

cd chaosmeta-inject-operator 
xgo test -v ./pkg/secret

Output:

=== RUN   TestInitProject
--- PASS: TestInitProject (0.18s)
=== RUN   TestGetSecret
--- PASS: TestGetSecret (0.00s)
=== RUN   TestGetMetadata
--- PASS: TestGetMetadata (0.00s)
=== RUN   TestListSecret
--- PASS: TestListSecret (0.00s)
=== RUN   TestCreatePutSecret
--- PASS: TestCreatePutSecret (0.00s)
=== RUN   TestDeleteSecret
--- PASS: TestDeleteSecret (0.00s)
PASS
ok      github.com/Tencent/bk-bcs/bcs-scenarios/bcs-gitops-vaultplugin-server/pkg/secret        3.235s

[tencentblueking-adm]

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