Allow changing an open connection if it's not owned

[stevendarby]

Fixes #30704

I went ahead and tried something, it's fine if it's not the direction you want to take though.

• I've read the guidelines for contributing and seen the walkthrough
• I've posted a comment on an issue with a detailed description of how I am planning to contribute and got approval from a member of the team [It's a very small change, I thought I'd try my luck]
• The code builds and tests pass locally (also verified by our automated build checks)
• Commit messages follow this format:

        Summary of the changes
        - Detail 1
        - Detail 2

        Fixes #bugnumber

• Tests for the changes have been added (for bug fixes / features)
• Code follows the same patterns and style as existing code in this repo

[ajcvickers]

Thanks @stevendarby!