fix: docker image content

[jmeridth]

• add .dockerignore to ensure non application files/test files don't get into the container image

Tested locally with the following commands:

➜ docker build . --tag test:1
➜ docker run -it --rm --name debug --entrypoint /bin/bash test:1

## inside container

root@3624b051f2c8:/action/workspace# ls -lah
total 44K
drwxr-xr-x 1 root root 4.0K May 27 13:11 .
drwxr-xr-x 1 root root 4.0K May 27 13:11 ..
-rw-r--r-- 1 root root 1.8K Jan  7 10:26 auth.py
-rw-r--r-- 1 root root 4.4K Mar 30 23:25 env.py
-rw-r--r-- 1 root root   68 Apr  4 04:04 requirements.txt
-rwxr-xr-x 1 root root  14K May 27 12:11 stale_repos.py

Pull Request

Proposed Changes

Readiness Checklist

Author/Contributor

• If documentation is needed for this change, has that been included in this pull request
• run make lint and fix any issues that you have introduced
• run make test and ensure you have test coverage for the lines you are introducing
• If publishing new data to the public (scorecards, security scan results, code quality results, live dashboards, etc.), please request review from @jeffrey-luszcz

Reviewer

• Label as either fix, documentation, enhancement, infrastructure, maintenance or breaking

[Copilot]

Pull Request Overview

This PR adds a .dockerignore file to prevent non-essential files (tests, caches, docs, IDE settings, etc.) from being included in the Docker image, slimming down the final build.

• Introduces a comprehensive set of ignore patterns for Python artifacts, logs, docs, IDE directories, dependency caches, Git files, and more.