Don't vendor rust-analyzer

Work around its dependency on fs_extra

Author: Aaron1011

src/bootstrap/dist.rs

@@ -913,7 +913,7 @@ impl Step for PlainSourceTarball {
             let mut cmd = Command::new(&builder.initial_cargo);
             cmd.arg("vendor")
                 .arg("--sync")
-                .arg(builder.src.join("./src/tools/rust-analyzer/Cargo.toml"))
+                //.arg(builder.src.join("./src/tools/rust-analyzer/Cargo.toml"))
                 .arg(builder.src.join("./compiler/rustc_codegen_cranelift/Cargo.toml"))
                 .current_dir(&plain_dst_src);
             builder.run(&mut cmd);