chore(LDS): Improve $relativeTime tests

[dplewis]

New Pull Request Checklist

• I am not disclosing a vulnerability.
• I am creating this PR in reference to an issue.

Issue Description

Adding missing test cases from #1344

Will add to the server for LiveQuery.

Related issue: #FILL_THIS_OUT

Approach

TODOs before merging

• Add tests
• Add entry to changelog
• Add changes to documentation (guides, repository pages, in-code descriptions)

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[codecov]

Codecov Report

Merging #1410 (647b3d2) into master (58bd796) will increase coverage by 0.70%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1410      +/-   ##
==========================================
+ Coverage   99.10%   99.81%   +0.70%     
==========================================
  Files          61       61              
  Lines        5943     5943              
  Branches     1350     1350              
==========================================
+ Hits         5890     5932      +42     
+ Misses         52       11      -41     
+ Partials        1        0       -1     

Impacted Files	Coverage Δ
src/OfflineQuery.js	100.00% <0.00%> (+13.59%)	⬆️

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