Add mamba env file

[AlexAndorra]

I noticed we don't have any mamba-compatible env file (LMK if that's on purpose), so I added one

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📚 Documentation preview 📚: https://pymc-marketing--556.org.readthedocs.build/en/556/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.37%. Comparing base (612b4d4) to head (25d31c3).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #556   +/-   ##
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  Coverage   91.36%   91.37%           
=======================================
  Files          21       21           
  Lines        2073     2075    +2     
=======================================
+ Hits         1894     1896    +2     
  Misses        179      179           

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[juanitorduz]

Nice! Maybe we can add it to the https://github.com/pymc-labs/pymc-marketing/blob/main/CONTRIBUTING.md guidelines? That is, show how to create the. virtual environment using this file?

And probably the quickstart https://www.pymc-marketing.io/en/stable/#quickstart :)

[AlexAndorra]

Will do @juanitorduz , will push here ASAP

[AlexAndorra]

Done @juanitorduz

[juanitorduz]

Thanks @AlexAndorra !