chore: replace various string paths with actual paths (#18109)

* chore: string paths should not be used outside test code

* format fixes

* Update benches/event.rs

Co-authored-by: Stephen Wakely <fungus.humungus@gmail.com>

* Update benches/event.rs

Co-authored-by: Stephen Wakely <fungus.humungus@gmail.com>

* parse dynamic strings before inserting to the event

* use event_path! for tracing fields

* Update benches/event.rs

Co-authored-by: Nathan Fox <fuchsnj@gmail.com>

* rebase on master and add comment

---------

Co-authored-by: Stephen Wakely <fungus.humungus@gmail.com>
Co-authored-by: Nathan Fox <fuchsnj@gmail.com>