[23.1] Optimize getting current user session

[mvdbeek]

We get all user session when logging in, this isn't necessary and does show up in a memray trace. I don't think it's a leak, but this is going to be more efficient.

How to test the changes?

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• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

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[jmchilton]

Shouldn't these optimizations target dev?

[mvdbeek]

Yes and no, we do want to run it on usegalaxy.org to see if it makes a difference, but if it doesn't fix the linear increase it could just go to dev, yes.