Bump rust embed (#2883)

This is a follow-up to a recent patch I've submitted to this crate to
improve compile time and runtime (in older versions file lookup was
essentially O(n) with respect to path count, now it's O(log n))

Release Notes:

- N/A

crates/zed/Cargo.toml

@@ -93,7 +93,7 @@ postage.workspace = true
 rand.workspace = true
 regex.workspace = true
 rsa = "0.4"
-rust-embed = { version = "6.8.1" }
+rust-embed.workspace = true
 serde.workspace = true
 serde_derive.workspace = true
 serde_json.workspace = true