proxy window.location for testing and extension overrides

[MichaelWest22]

Description

To allow loc coverage testing of hard reloads and refreshes I've proxied window.location into htmx.location that is used for .reload() and setting href. This can then be replaced if needed to allow full testing of the reload features and also this would allow future extensions to override page reloading if required.

Also found instances of document.location usage which should all be just location to minify code.

Corresponding issue:

Testing

Added new tests for HX-Refresh and HX-Redirect and history cache miss

Checklist

• I have read the contribution guidelines
• I have targeted this PR against the correct branch (master for website changes, dev for
  source changes)
• This is either a bugfix, a documentation update, or a new feature that has been explicitly
  approved via an issue
• I ran the test suite locally (npm run test) and verified that it succeeded