* chore: Overhaul Dockerfile for sandboxes using Docker best practices
* Reduce image size by installing and removing prerequisite packages
in the same layer.
* Rearrange stages to use docker-production settings for non-dev
targets. docker-production settings already inherit production
settings and can be used to override configuration specific to
containers e.g. logging.
* chore: write improved Dockerfile2 just for testing
* chore: update development stage to not run as app user
* fix: wrap settings configuration in if statement
* chore: update Dockerfile.
* Moved code COPY command down in the base stage.
* Added comments.
Co-authored-by: Alie Langston <alangsto@wellesley.edu>
- Moving xmodule folder to root as we're dissolving sub-projects of common folder in edx-platform
- More info: https://openedx.atlassian.net/browse/BOM-2579
- -e common/lib/xmodule has been removed from the requirements as xmodule has itself become the part of edx-platform and not being installed through requirements
- The test files common/lib/xmodule/test_files/ have been removed as they are not being used anymore
