chore: Fix violations of elided_named_lifetimes (#18330)

I compile Zed from nightly build pretty often and I've noticed that
we're getting a few hits on new rustc lint:
https://github.com/rust-lang/rust/pull/129207

Release Notes:

- N/A

crates/project/src/project.rs

@@ -3954,7 +3954,7 @@ impl Project {
     pub fn supplementary_language_servers<'a>(
         &'a self,
         cx: &'a AppContext,
-    ) -> impl '_ + Iterator<Item = (LanguageServerId, LanguageServerName)> {
+    ) -> impl 'a + Iterator<Item = (LanguageServerId, LanguageServerName)> {
         self.lsp_store.read(cx).supplementary_language_servers()
     }