Unit readings test cleanup

[Better-Code-Saul-E]

Description

Migrated src/server/test/routes/unitReadingsRouteTests.js to match the newer ParamsTest.js route parameter testing style and renamed the file to unitReadingsParamsTest.js.

• Renamed the test file to unitReadingsParamsTest.js for naming consistency.
• Updated validation checks to use standard validation helper.
• Refactored HTTP request queries to include required parameter like 'readingInterval' and UTC time intervals.
• Cleanedup unsused imports and dead code.

Fixes #1662

Type of change

• Note merging this changes the database configuration.
• This change requires a documentation update

Checklist

• I have followed the OED pull request ideas
• I have removed text in ( ) from the issue request
• You acknowledge that every person contributing to this work has signed the OED Contributing License Agreement and each author is listed in the Description section.

Limitations

N/A

[huss]

@Better-Code-Saul-E Thank you for another contribution. It will be about a week before I can review this work. I didn't know if you saw this but the tests and/or checks failed. FYI.

[Better-Code-Saul-E]

Found the bug! I added an await when creating the test meter.