refactor: consistent use of DataReader

[synchon]

• description of feature/fix
• tests added/passed
• add an entry for the latest changes

This PR removes datareader / DataReader naming convention issue in the codebase and adopts DataReader to make the code consistent with the docs.

[codecov]

Codecov Report

Merging #227 (ef739b5) into main (84ed73b) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #227   +/-   ##
=======================================
  Coverage   93.60%   93.60%           
=======================================
  Files          80       80           
  Lines        3458     3458           
  Branches      650      650           
=======================================
  Hits         3237     3237           
  Misses        144      144           
  Partials       77       77           

Flag	Coverage Δ
docs	100.00% <ø> (ø)
junifer	93.60% <ø> (ø)

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Impacted Files	Coverage Δ
junifer/api/decorators.py	100.00% <ø> (ø)
junifer/datareader/default.py	100.00% <ø> (ø)
junifer/markers/collection.py	100.00% <ø> (ø)

[github-actions]

PR Preview Action v0.0.2-79-ge40ada5e
🚀 Deployed preview to https://juaml.github.io/junifer/pr-preview/pr-227/
on branch gh-pages at 2023-05-16 14:16 UTC