make linter happy

Author: TommyCpp

opentelemetry-otlp/src/lib.rs

@@ -162,7 +162,7 @@
 //!     # #[cfg(all(feature = "metrics", feature = "grpc-tonic"))]
 //!     # {
 //!     let export_config = ExportConfig {
-//!         endpoint: Some("http://localhost:4317".to_string()),
+//!         endpoint: "http://localhost:4317".to_string(),
 //!         timeout: Duration::from_secs(3),
 //!         protocol: Protocol::Grpc
 //!     };