Add config setting to avoid adding trailing slash to URLs

[samuelcolvin]

Preparation for fixing https://github.com/pydantic/pydantic/issues/7186

[codspeed-hq[bot]]

CodSpeed Performance Report

Merging #1719 will not alter performance

_{Comparing no-trailing-slash (660b112) with main (e43c144)}

Summary

✅ 157 untouched benchmarks

[davidhewitt]

Studying this, I think that it's possibly more complex than it needs to be and that the main problem case is that "empty" path gets replaced with /.

So I think we might instead just need a simpler config option like normalize_empty_path = False (or preserve_empty_path = True)? I am planning to try a reboot of this PR in that vein tomorrow.

[davidhewitt]

Superseded by #1789