docs: Move default values to fix settings anchor links

[asweigart]

Also fixed typos in default values. See: #3456

Pull Request Checklist

• Ensured tests pass and (if applicable) updated functional test output
• Conformed to code style guidelines by running appropriate linting tools
• Added tests for changed code
• Updated documentation for changed code

[asweigart]

The failing code tests were there before my docs-only change, but the doc test failed because my change to SLUG_REGEX_SUBSTITUTIONS should be:

   The default is:

   .. parsed-literal::

       [
           (r'[^\\w\\s-]', ''),  # remove non-alphabetical/whitespace/'-' chars
           (r'(?u)\\A\\s*', ''),  # strip leading whitespace
           (r'(?u)\\s*\\Z', ''),  # strip trailing whitespace
           (r'[-\\s]+', '-'),  # reduce multiple whitespace or '-' to single '-'
       ]

I'm... not quite sure how to update the PR in a way to get it submitted correctly. (I installed sphinx and sphinxext-opengraph and what not to try to locally build the docs but kept failing.) Could someone on the Pelican team do the one-file change for this doc update?

[pauloxnet]

LGTM

[justinmayer]

I fixed the test errors in a separate pull request and updated this branch, so that problem is resolved.

There were multiple causes of the documentation build failures: (1) inline literal marks can't be used on multi-line blocks, and (2) a needed reference had been removed. I fixed both of those problems and will now squash and merge this PR.

Many thanks to @asweigart for enabling linking to individual settings, something I have wanted to be rectified for a long time. Much appreciated! 👍