Docs Error in heartrateanalysis.rst

[gianttt97]

In ./docs/heartrateanalysis.rst or https://python-heart-rate-analysis-toolkit.readthedocs.io/en/latest/heartrateanalysis.html, there is a reference A complete description of the algorithm can be found in: <ref embedded paper> . The problem is that if <ref embedded paper> misses some paper.

[paulvangentcom]

Thank you, I will update that