fix(dashmate): handle missing docker.sock group write permissions for helper

[pshenmic]

Issue being fixed or feature implemented

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Breaking Changes

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• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have added or updated relevant unit/integration/functional/e2e tests
• [ ] I have added "!" to the title and described breaking changes in the corresponding section if my code contains any
• [ ] I have made corresponding changes to the documentation if needed

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