Merge #3996

3996: Fix path for proc-macro in nightly / stable release r=matklad a=edwin0cheng

I messed up that I forget we use different executable names for nightly / stable release, I changed to use the current executable name instead.

Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>

crates/rust-analyzer/src/cli/load_cargo.rs

@@ -75,9 +75,7 @@ pub(crate) fn load_cargo(
     let proc_macro_client = if !with_proc_macro {
         ProcMacroClient::dummy()
     } else {
-        let mut path = std::env::current_exe()?;
-        path.pop();
-        path.push("rust-analyzer");
+        let path = std::env::current_exe()?;
         ProcMacroClient::extern_process(&path, &["proc-macro"]).unwrap()
     };
     let host = load(&source_roots, ws, &mut vfs, receiver, extern_dirs, &proc_macro_client);