Strip double quotes from umask check

[pkishino]

Breaking change

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Proposed change

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Type of change

• Bugfix (non-breaking change which fixes an issue)
• New feature (which adds functionality to this container)
• Breaking change (fix/feature causing existing functionality to break)

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue: relates to #
• Link to documentation updated (if done separately): https://...

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated