feat: add keepdeps.go to preserve mod clean in opensource version

[HynoR]

What this PR does / why we need it?

xpack 专业版应该是用了两个额外的依赖，开源版本因为没这连个依赖，所以go mod tidy会移除，导致其他版本ci编译失败。
添加占位文件避免其他贡献者 tidy 误删除

此 pr 比较 hack，需要讨论是否需要这么做

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[ssongliu]

pr #11751 下面已经有这个修改了