fix shannon entropy broken link

[icmeyer]

Description

Self explantory title, fixed a broken link in the docs

Checklist

• [x ] I have performed a self-review of my own code
• I have run clang-format (version 15) on any C++ source files (if applicable)
• I have followed the style guidelines for Python source files (if applicable)
• [x ] I have made corresponding changes to the documentation (if applicable)
• I have added tests that prove my fix is effective or that my feature works (if applicable)

[paulromano]

Thanks!