Update contributing guidelines to include pre-commit install

[VMRuiz]

No description provided.

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (a641cbf) 76.41% compared to head (0252825) 76.41%.

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Additional details and impacted files

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  Coverage   76.41%   76.41%           
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  Files          76       76           
  Lines        3193     3193           
  Branches      378      378           
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  Hits         2440     2440           
  Misses        683      683           
  Partials       70       70           

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[kmike]

I'm not sure how requirements.txt are organized, but probably it'd be better to make an explicit requirement-dev.txt file, as not all of these requirements are needed to run spidermon.

Also, it seems some of the requirements which are here are not in setup.py, e.g. itemadapter is not in setup.py install_requires (it's in test_requires for some reason).

[VMRuiz]

Yeah, the package requirements are weirdly structured, we could open a new issue to fix that

[kmike]

Makes sense; we don't need to fix it in this PR.

Not having itemadapter in install_requires looks like a separate issue, I think it's a bug (no need to fix it in this PR either).

[kmike]

👍