Updated release notes following backport of a407b84. Refs #23365.
Skip another test if sqlparse is not available

Refs #23426
Fixed #23627 -- Allowed register_lookup to work as a decorator.
Fixed #23612 -- Normalized fixuture paths to allow referencing relative paths on Windows.
Avoided requiring sqlparse for a test.

Refs #23426. Thanks Markus Holtermann for the suggestion.
Converted GIS lookups to use the new Lookup API

Thanks Tim Graham, Anssi Kääriäinen and Marc Tamlyn for the
reviews.
Converted GIS lookups for Oracle
Updated my AUTHORS entry.
Fixed #23625 -- Removed CacheClass shim
Fixed #23613 -- Deprecated django.utils.checksums
Fixed #23623 -- Reduced memory consumption when generating ModelChoiceField choices
Added Jaap Roes to AUTHORS
Fixed #23616 - Fixed generic relations in ModelAdmin.list_filter.

Thanks ranjur for reporting bug, timgraham for review,
and collinanderson for contributing tips.
Fixed #23631 -- Removed outdated note on MySQL timezone support.

Thanks marfire for the report.
Added my bio to team docs.
Fixed a tuple/int comparison in spatialite backend

On Python 3, comparing tuple with int raises a TypeError.
Fixed two more tuple/int comparisons in gis tests

Refs 63ff417746.
Fixed #23639 -- Fixed doc error in RegexValidator.regex

Thanks to @claudep for the report and the original patch.
Fixed #23642 -- Made LocMemCache.incr() thread-safe as documented
Fixed #23063 -- Convert \n and \r to \r\n when using the SMTP backend as per RFC.