Revert "Revert "language: Remove buffer fingerprinting (#9007)"" (#9671)

This reverts commit caed275fbf.

NOTE: this should not be merged until #9668 is on stable and the
`ZedVersion#can_collaborate` is updated to exclude all clients without
that change.

Release Notes:

- N/A

---------

Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>

crates/copilot/src/copilot.rs

@@ -1255,7 +1255,6 @@ mod tests {
             &self,
             _: BufferId,
             _: &clock::Global,
-            _: language::RopeFingerprint,
             _: language::LineEnding,
             _: Option<std::time::SystemTime>,
             _: &mut AppContext,