test(aws): Add default Boto3 credentials

[jfagoagas]

Description

• Add default environment variables for testing and mocking with AWS Boto3 and moto. Rationale: https://docs.getmoto.org/en/latest/docs/getting_started.html#recommended-usage
• Add pytest-env plugin to set those environment variables

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (355f589) 85.87% compared to head (78b949c) 85.91%.
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3404      +/-   ##
==========================================
+ Coverage   85.87%   85.91%   +0.03%     
==========================================
  Files         594      594              
  Lines       19027    19027              
==========================================
+ Hits        16340    16347       +7     
+ Misses       2687     2680       -7     

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[sergargar]

🔝