Change image to 3.11.1-slim

[ady-1811]

Description

Since Debian buster has reached EOL, RUN apt-get update && apt-get install -y gcc libpq-dev sqlite3 does not work anymore. To fix this, the image has been updated to 3.11.1-slim instead

Fixes # (issue)

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Type of Change

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• This change requires a documentation update

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• Test B

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Checklist

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