docs: update related packages sections

[stdlib-bot]

This PR

• updates the related packages section of READMEs to include links to related packages.

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
random/array/cauchy	$\\color{green}212/212$ $\\color{green}+100.00\\%$	$\\color{green}3/3$ $\\color{green}+100.00\\%$	$\\color{green}0/0$ $\\color{green}+100.00\\%$	$\\color{green}212/212$ $\\color{green}+100.00\\%$

The above coverage report was generated for the changes in this PR.