Add deterministic and statistical test for RMC density and spindensity check

[Hyeondeok-Shin]

Proposed changes

This PR is to add missing RMC test for density and spin-density check. Deterministic and statistical tests are included for 1x1x1 diamond.

What type(s) of changes does this code introduce?

• Other (please describe): Add test

Does this introduce a breaking change?

• No

What systems has this change been tested on?

Intel Xeon, Theta, Summit

Checklist

Update the following with a yes where the items apply. If you're unsure about any of them, don't hesitate to ask. This is
simply a reminder of what we are going to look for before merging your code.

• Yes. This PR is up to date with current the current state of 'develop'
• No. Code added or changed in the PR has been clang-formatted
• Yes. This PR adds tests to cover any new code, or to catch a bug that is being fixed
• No. Documentation has been added (if appropriate)

[prckent]

It looks like this PR has coincided with a macos actions change, since the macos build now fails. Possibly with a real bug.

I'll start the other tests in the interim in case updates to error bars are needed.

[prckent]

Test this please

[prckent]

Thanks Hyeondeok. We can tackle the macos problem independently.

[prckent]

Test this please