give actuator src a ghost cell and populate it (interior)

[mbkuhn]

Summary

Currently, sampling the actuator src term is erroneous because it does not have any ghost cells. This PR gives the actuator src term a ghost cell and populates it in interior boundaries to ensure that it can be sampled properly.

Pull request type

• [x] Bugfix
• [ ] Feature
• [ ] Code style update (formatting, renaming)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] Documentation content changes
• [ ] Other (please describe):

Checklist

The following is included:

• [ ] new unit-test(s)
• [ ] new regression test(s)
• [ ] documentation for new capability

This PR was tested by running:

• the unit tests
  • [ ] on GPU
  • [ ] on CPU
• the regression tests
  • [ ] on GPU
  • [ ] on CPU

Additional background

I think that this is related to the changes in #1030, but I don't think it's redundant.

[mbkuhn]

Videos from sampled actuator src without the changes in this PR (errors due to referencing ghost indices that do not exist, leading to accessing values from another part of the array) :

https://github.com/Exawind/amr-wind/assets/31661049/072d078a-f992-46b9-87ac-158cc38fa8f1

https://github.com/Exawind/amr-wind/assets/31661049/3dd25e6c-4f6e-4996-8c84-bd39b906123d

[mbkuhn]

Screenshot with the changes from this PR: