Fix docker executable not being quoted in shell script templates

[gudmundur-heimisson]

PR Checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

What is the current behavior?

If the docker executable path contains a space (for example when running under WSL), then all of the generated shell templates that use the docker executable fail with a file not found error.

Issue Number: N/A

What is the new behavior?

Execution will now succeed for docker executables where the path contains a space.

Does this PR introduce a breaking change?

• Yes
• No

Other information

Tested this locally on my WSL2 machine and docker rules now work.

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[gudmundur-heimisson]

I have just signed the CLA thing, not sure how to rerun the check.

EDIT: Figured it out, diregard this comment.

[gudmundur-heimisson]

Friendly ping.