Update JUnit to 4.13.2

[mccartney]

Upgrading to JUnit 4.13.2 for no specific reason other than staying up to date.

[stleary]

What problem does this code solve?
Just updating the junit version for unit tests.

Risks
Low

Changes to the API?
N/A

Will this require a new release?
No

Should the documentation be updated?
No

Does it break the unit tests?
N/A

Was any code refactored in this commit?
N/A

Review status
APPROVED
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