What are you trying to accomplish?

Allows overwriting the read and open timeout values for interactions with the docker registry using two separate environment variables

What issues does this affect or fix?

I do not have any issue in the tracker, but I noticed this need while using dependabot-core with slow private registries

If there were multiple ways to approach the problem, why did you pick this one?

Initially, I considered using the existing environment variables defined here :

But I noticed that the default values there are different and I figured that separate environment properties may be better

Checklist

• I have run the complete test suite to ensure all tests and linters pass.
• I have thoroughly tested my code changes to ensure they work as expected, including adding additional tests for new functionality.
• I have written clear and descriptive commit messages.
• I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• I have ensured that the code is well-documented and easy to understand.