chore(main): release 6.3.0 (#132)

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Merge pull request #119 from mdp/mdp/constant_generate

Make generate more constant time

Merge pull request #118 from mdp/mdp/remove_docs_folder

Remove old rubydocs folder, fix README badge

Update to expand compatibility with Ruby 3.

This was only a change to the gemspec, no code changes were necessary.

Update Readme regarding 6.0 dropping Ruby <2.3

Bump to v5.1.0

Update to v5.0.0 due to breaking change to 'Base32.random' API

Udpate to v4.1.0

Update to fix incorrect gemspec dependency