tests: add analytic kernel herding tests.

[pc532627]

Refs: #786
Closes: #786

PR Type

• Documentation content changes
• Tests

Description

Kernel herding now has an analytical test (for the case where unique is set to true and when it is set to false) and these tests have been used to showcase to a user a minimal worked example in the documentation.

How Has This Been Tested?

Two new tests added and pass.

Does this PR introduce a breaking change?

N/A

Checklist before requesting a review

• I have made sure that my PR is not a duplicate.
• My code follows the style guidelines of this project.
• I have commented my code, particularly in hard-to-understand areas.
• I have performed a self-review of my code.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.

[github-actions]

Performance review

Commit d5a9346 - Merge 5e9c46e into 41b3922

No significant changes to performance.

[github-actions]

Performance review

Commit a08a504 - Merge 6d163e3 into ba4a3c1

No significant changes to performance.

[github-actions]

Performance review

Commit 084a53d - Merge 081d321 into ba4a3c1

No significant changes to performance.