ComputeClass request downscaling for overprovisioning (#2381)

[keyallis]

2381

Add support for scaling down memory requests for acorns in relation to memory limits. We handle ComputeClasses that do not have this field set (ie legacy ComputeClasses) as having a 1:1 mapping. This means all existing tests should continue to work and behave as expected, so all new tests are only used to cover the new field itself.

Checklist

• [ ] The title of this PR would make a good line in Acorn's Release Note's Changelog
• [ ] The title of this PR ends with a link to the main issue being address in parentheses, like: This is a title (#1216). Here's an example
• [ ] All relevant issues are referenced in the PR description. NOTE: don't use GitHub keywords that auto-close issues
• [ ] Commits follow contributing guidance
• [ ] Automated tests added to cover the changes. If tests couldn't be added, an explanation is provided in the Verification and Testing section
• [ ] Changes to user-facing functionality, API, CLI, and upgrade impacts are clearly called out in PR description
• [ ] PR has at least two approvals before merging (or a reasonable exception, like it's just a docs change)

[g-linville]

I'm just now starting to look at the code, but one thing I am noticing is that scalar needs to be replaced with scaler everywhere it appears. We're calling it a "scaler" because it determines the scale of the memory request in comparison to the limit. Mathematically speaking it is also a "scalar" since it is a single numerical value and not a vector, but that is not what we should name it lol.