User-Agent Detection Fix + New-Style rewriting on by default + Dependency Update (2.6.6)

[ikreymer]

Description

Fix user-agent detection to not user werkzeug (due to obsolete package), and use ua_parser

Motivation and Context

• werkzeug user-agent is no longer supported (Python 3.8 / 3.9 dependency problems (werkzeug / gevent/greenlet) #704) and returns incorrect results on browsers >100
• use ua_parser to detect browser version, use old-style location rewriting only for detected older browsers, default to newer rewriting by default User-Agent sniffing broken by Chrome 100 and Firefox 100 #707

Screenshots (if appropriate):

Types of changes

• Replay fix (fixes a replay specific issue)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added or updated tests to cover my changes.
• All new and existing tests passed.