fix: Replace Java wildcard imports with explicit imports.

[bdferris-v2]

Per discussion in #1146, I am cleaning up a few "import package.*" wildcard imports in the codebase.

Please make sure these boxes are checked before submitting your pull request - thanks!

• Run the unit tests with gradle test to make sure you didn't break anything
• Format the title like "feat: [new feature short description]". Title must follow the Conventional Commit Specification(https://www.conventionalcommits.org/en/v1.0.0/).
• Linked all relevant issues

[barbeau]

👍

[isabelle-dr]

Thanks, @bdferris-v2!