Update all commented out regression tests #397
Description
In a number of files there are unit tests that were commented out a few years ago, or were set with a very lax atol or rtol to ensure false positives were not triggered.
The context is that the random number generator in Julia, with the default RNG changing around 3 years ago and it seems some files were simply commented out to fix them rather than updating to the new RNG values. I think we can assume that the RNG will be stable from now on, or that a new task can be done to update it otherwise.
This issue should go through all files with unit test blocks and:
- Ensure all commented out test values are fixed to the new values/etc.
- Move the rtol/atol to be more strict to ensure we don't miss a regression
- Doublecheck that the random seed is set at the beginning for reproducibility