Add data detection for heap sensor

[bachya]

Describe what the PR does:

SSIA. Ecowitt devices with upgradable firmware are starting to roll this data point out.

Does this fix a specific issue?

N/A

Checklist:

• Confirm that one or more new tests are written for the new functionality.
• Run tests and ensure everything passes (with 100% test coverage).
• Update README.md with any new documentation.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (2b80fb7) 100.00% compared to head (3ab6e63) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##               dev      #845   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           31        32    +1     
  Lines         1759      1769   +10     
=========================================
+ Hits          1759      1769   +10     

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