Adding description of EOL time node in DB

[john-science]

What is the change?

Adding description of the new EOL time node in DB.

Why is the change being made?

This should have been added when the EOL change was made. But it's just a documentation change.

close #1782

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Checklist

• [x] This PR has only one purpose or idea.
• [x] Tests have been added/updated to verify any new/changed code.

• [x] The code style follows good practices.
• [x] The commit message(s) follow good practices.

• [x] The release notes have been updated if necessary.
• [x] The documentation is still up-to-date in the doc folder.
• [x] The dependencies are still up-to-date in pyproject.toml.