Env vars

[diemol]

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Description

This prefixes all environment variables with SE_ in order to make it simple for Dynamic Grid to identify them and pass them along to the child containers.

Motivation and Context

So it is possible to configure the child containers in Dynamic Grid. Please note, the Grid code still needs to read the env vars, which will be done in the upstream repository.

This PR helps with #1319

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.