Fix binary name for extension CLI (#9591)

This PR fixes the binary name for the extension CLI.

This was originally done in #9541, but got accidentally reverted in
#9549.

Release Notes:

- N/A

crates/extension_cli/Cargo.toml

@@ -8,6 +8,10 @@ license = "GPL-3.0-or-later"
 [lints]
 workspace = true
 
+[[bin]]
+name = "zed-extension"
+path = "src/main.rs"
+
 [dependencies]
 anyhow.workspace = true
 clap = { workspace = true, features = ["derive"] }