TST: fix hist file test timeouts

[tangkong]

Description

• attempt to figure out why history file tests are failing

Motivation and Context

This test has been timing out on python3.12 and I want to find out why. Perhaps splitting it out will help de-conflict things
See this failure

Locally splitting the single history file test case into 3 separate tests resulted in each taking around 7s. With a timeout of 30s, it makes sense that this sometimes fails. (prior to this change, that test was taking ~23s)

I re-ran the ci python 3.12 conda tests multiple times, and it's passed each time 🤷

How Has This Been Tested?

Interactively, with little success in reproducing the failures seen on CI

Where Has This Been Documented?

This PR

Pre-merge checklist

• Code works interactively (a real hutch config file can be loaded)
• Code contains descriptive docstrings, including context and API
• New/changed functions and methods are covered in the test suite where possible
• Test suite passes locally
• Test suite passes on GitHub Actions
• Ran docs/pre-release-notes.sh and created a pre-release documentation page
• Pre-release docs include context, functional descriptions, and contributors as appropriate

[tangkong]

of course there's no problem here. 🙃

[tangkong]

I'll put this up for review and see if it helps. I didn't really solve the underlying problem, but best I could see nothing actually hangs here forever. (locally or on CI)

[ZLLentz]

Forward progress!