op-mode: T7527: move assorted embedded shel snippets to script files

[dmbaturin]

Change summary

Use of embedded shell scripts is incompatible with the idea to execute op mode commands through a wrapper. This is the first PR in a series that fix that issue.

The connection between the commands involved is quite tenuous: they are (arguably) more frequently used and don't fit a wider pattern.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

Related PR(s)

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Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

👍
No issues in PR Title / Commit Title

[sever-sever]

Fixes part of the op-mode commands

[c-po]

Cleanup and refactoring of op-mode parts. It even cleans up some mess introduced by myself.

[github-actions]

CI integration 👍 passed!

Details

CI logs

• CLI Smoketests (no interfaces) 👍 passed
• CLI Smoketests (interfaces only) 👍 passed
• Config tests 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed