Validate SUBACK/UNSUBACK reason code count

[sfod]

This is a follow-up for #431

Validate SUBACK/UNSUBACK reason code count against the acknowledged request. When a mismatch detected, the client fails the offending operation and disconnects sending a DISCONNECT with a reason code.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 95.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 84.66%. Comparing base (e35b9ca) to head (f4d459f).

Files with missing lines	Patch %	Lines
source/v5/mqtt5_client.c	95.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #432   +/-   ##
=======================================
  Coverage   84.65%   84.66%           
=======================================
  Files          26       26           
  Lines       11093    11109   +16     
=======================================
+ Hits         9391     9405   +14     
- Misses       1702     1704    +2     

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