Fix tests for pygments 2.14

[Gallaecio]

See pygments/pygments#2313

[codecov]

Codecov Report

Merging #5783 (34286e3) into master (deaf1fb) will increase coverage by 3.93%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5783      +/-   ##
==========================================
+ Coverage   84.82%   88.76%   +3.93%     
==========================================
  Files         162      162              
  Lines       10974    10974              
  Branches     1795     1795              
==========================================
+ Hits         9309     9741     +432     
+ Misses       1394      950     -444     
- Partials      271      283      +12     

Impacted Files	Coverage Δ
scrapy/extensions/feedexport.py	95.12% <0.00%> (+3.89%)	⬆️
scrapy/squeues.py	100.00% <0.00%> (+4.54%)	⬆️
scrapy/pipelines/media.py	98.58% <0.00%> (+5.67%)	⬆️
scrapy/utils/test.py	66.21% <0.00%> (+9.45%)	⬆️
scrapy/core/downloader/contextfactory.py	87.03% <0.00%> (+11.11%)	⬆️
scrapy/core/http2/protocol.py	83.41% <0.00%> (+49.24%)	⬆️
scrapy/core/downloader/handlers/http2.py	100.00% <0.00%> (+54.92%)	⬆️
scrapy/core/http2/agent.py	96.38% <0.00%> (+60.24%)	⬆️
scrapy/core/http2/stream.py	91.32% <0.00%> (+64.73%)	⬆️
scrapy/pipelines/images.py	97.05% <0.00%> (+70.58%)	⬆️