fix: ssh formatting exception bug when executing commands

[dbbDylan]

What type of PR is this?

/kind bug

What this PR does / why we need it:

• String formatting directly by fmt.Sprintf may cause unexpected error when executing a single command as a result of multiple double-quote transpositions. The more safe way is to use exec.Command function.
• Fix from file:// to file:/// in init_repository.yaml

For more information on release notes see: https://github.com/kubernetes/community/blob/master/contributors/guide/release-notes.md
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- fix: ssh formatting exception bug when executing commands
- fix: from `file://` to `file:///` in `init_repository.yaml`

[kubesphere-prow]

This PR has multiple commits, and the default merge method is: squash.
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[dbbDylan]

This way can correctly execute multi-line commands, but use one nolint:gosec annotation to avoid lint error.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[kubesphere-prow]

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This pull-request has been approved by: dbbDylan

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