Completed test case CG2

[BrendenHaskins]

Description

Adds mocha test for test case CG2 into readingsCompareGroupQuantity.js (src/server/test/web)
This PR would require a change in DesignDocs/testing/testing.md to show CG2 as complete.
With the help of @lukeckk, @RaiuXL

Partially Addresses #962

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

This is only one of the compare group tests.