Replace Union type with pipe

[evan-palmer]

Checklist

• [x] I have performed a thorough review of my code
• [x] I have sufficiently commented my code
• [x] The implementation follows the project style conventions
• [x] All project unit tests are passing
• [x] If necessary, documentation has been provided or updated to discuss the changes
• [x] System integration tests are performed successfully
• [x] Any new dependencies have been added to the requirements list
• [x] Any changes that will not be completed or bugs that have been introduced have been added as issues

Changes Made

The existing implementation utilized the Union type hint inconsistently. Specifically, there were situations that utilized the | None union, but others that specified the Union type. This PR replaces all instances of Union with the | operator.

Associated Issues

Closes #88

Files Changes

• Changed all files that utilized the Union type hint

Testing

Testing was performed by running mypy against the system implementation to verify that no type errors were raised.

Issues Introduced

N/A