MNT: Prepend src for the coverage path

[jhlegarreta]

Prepend src for the coverage path; otherwise, the coverage of the modules analysis.featuring.py, analysis.filtering.py, and cli.run.py are reported to be 0%, even if there they are covered extensively by existing tests.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.96%. Comparing base (b7f15dc) to head (ef8ea47).

Additional details and impacted files

@@             Coverage Diff             @@
##             main      #23       +/-   ##
===========================================
+ Coverage   47.01%   95.96%   +48.94%     
===========================================
  Files          15       15               
  Lines         570      570               
  Branches       35       35               
===========================================
+ Hits          268      547      +279     
+ Misses        297       16      -281     
- Partials        5        7        +2     

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[jhlegarreta]

So coverage has increased from 47%

in e.g. the recent PR #22, to 95% in this PR:

without adding any new tests.

I thought that this may be related to the use of click commands, as the module that contains the commands, run.py, is not being covered. However, I have realized that there are modules such as filtering.py and featuring.py that do not depend on click for which the reported coverage was also 0% before this patch set.

Trying to gather information:
https://discuss.python.org/t/codecov-not-reporting-expected-coverage-when-using-package-name/105368, before I explore opening an issue in the coverage repository: https://github.com/coveragepy/coveragepy/issues