what is the cause of airflow deployment error on docker image

The problem I’m having

I am pushing a dbt model query change to GitHub, and PR’s auto check returns error on check lint and unit tests.
The error is about dockerfile failing to run apt-get update. We custom create our own dockerfile.
It is an ad-hoc error, everything was still good earlier.
Any suggestions on finding root cause and solution to fix it are welcomed.

The context of why I’m trying to do this

What I’ve already tried

Some example code or error messages

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