[Pagten]

This one-liner PR provides a trivial core::error::Error implementation for MqttError. The advantage of implementing the Error trait for MqttError is that it makes the type compatible with various error handling libraries, such as anyhow and thiserror.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.91%. Comparing base (b1cc4d2) to head (d181ee6).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #59   +/-   ##
=======================================
  Coverage   90.91%   90.91%           
=======================================
  Files          55       55           
  Lines        7486     7486           
=======================================
  Hits         6806     6806           
  Misses        680      680           

Files with missing lines	Coverage Δ
src/mqtt/result_code.rs	100.00% <ø> (ø)

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[redboltz]

@Pagten , Thank you for sending the PR.
Looks good to me. Merged(Add tests and update version on #60)