Update protected_header type from bytes to dict.

[dajiaji]

No description provided.

[codecov]

Codecov Report

Merging #34 (9297958) into main (7f25f12) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #34      +/-   ##
==========================================
+ Coverage   94.34%   94.38%   +0.03%     
==========================================
  Files          14       14              
  Lines         866      872       +6     
  Branches      199      203       +4     
==========================================
+ Hits          817      823       +6     
  Misses         36       36              
  Partials       13       13              

Impacted Files	Coverage Δ
cwt/cose.py	69.15% <100.00%> (+0.58%)	⬆️
cwt/recipient.py	100.00% <100.00%> (ø)

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