Proposed changes

Additional Testing of Energy Density Estimator

Added:
Homogenous Electron Gas tests for batched vmc and dmc.
The energy density should be approximately homogenous.
The energy should be the same whether the coulomb AA and other hamiltonian operators should produce the same results whether batched per particle eval is taken or not. It is taken when the energy density estimator is on

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

• Testing changes (e.g. new unit/integration/performance tests)

Does this introduce a breaking change?

• No

What systems has this change been tested on?

osx dev laptop

Checklist

• • I have read the pull request guidance and develop docs
• • This PR is up to date with the current state of 'develop'
• • Code added or changed in the PR has been clang-formatted
• • This PR adds tests to cover any new code, or to catch a bug that is being fixed
• • Documentation has been added (if appropriate)