test(DataStore): add missing tests

[ckohen]

Please describe the changes this PR makes and why it should be merged:

Add the rest of the tests for DataStore 😄

Status and versioning classification:

[codecov]

Codecov Report

Merging #165 (39ae427) into main (516bc3b) will increase coverage by 2.86%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #165      +/-   ##
==========================================
+ Coverage   68.65%   71.52%   +2.86%     
==========================================
  Files          19       19              
  Lines         906      906              
  Branches      221      215       -6     
==========================================
+ Hits          622      648      +26     
+ Misses        282      256      -26     
  Partials        2        2              

Impacted Files	Coverage Δ
src/DataStore.ts	100.00% <0.00%> (+60.46%)	⬆️

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