Add custom attribute support to the article spider.

[wRAR]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.93%. Comparing base (5a930c7) to head (dc11983).
⚠️ Report is 33 commits behind head on main.

Files with missing lines	Patch %	Lines
zyte_spider_templates/spiders/article.py	83.33%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #109   +/-   ##
=======================================
  Coverage   95.93%   95.93%           
=======================================
  Files          26       26           
  Lines        2609     2610    +1     
=======================================
+ Hits         2503     2504    +1     
  Misses        106      106           

Files with missing lines	Coverage Δ
zyte_spider_templates/spiders/article.py	85.97% <83.33%> (+0.08%)	⬆️

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[kmike]

The code looks good, but we should have more tests for this feature before merging & releasing it.

[Gallaecio]

Would something basic in line with test_crawl from https://github.com/zytedata/zyte-spider-templates/pull/117/files do the job, or are you thinking of something more?