Disable Referer by default for Zyte API requests

[Gallaecio]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 88.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 97.75%. Comparing base (aebc3f4) to head (be233fb).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
scrapy_zyte_api/_middlewares.py	87.50%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #239      +/-   ##
==========================================
- Coverage   97.90%   97.75%   -0.16%     
==========================================
  Files          14       14              
  Lines        1622     1647      +25     
  Branches      297      301       +4     
==========================================
+ Hits         1588     1610      +22     
- Misses         14       17       +3     
  Partials       20       20              

Files with missing lines	Coverage Δ
scrapy_zyte_api/__init__.py	100.00% <ø> (ø)
scrapy_zyte_api/addon.py	98.14% <100.00%> (+0.03%)	⬆️
scrapy_zyte_api/_middlewares.py	96.05% <87.50%> (-1.61%)	⬇️