simplify async trait impl (open-telemetry#2692)

Author: gruebel

opentelemetry-sdk/src/logs/log_processor.rs

@@ -88,12 +88,8 @@ pub(crate) mod tests {
     }
 
     impl LogExporter for MockLogExporter {
-        #[allow(clippy::manual_async_fn)]
-        fn export(
-            &self,
-            _batch: LogBatch<'_>,
-        ) -> impl std::future::Future<Output = OTelSdkResult> + Send {
-            async { Ok(()) }
+        async fn export(&self, _batch: LogBatch<'_>) -> OTelSdkResult {
+            Ok(())
         }
 
         fn shutdown(&mut self) -> OTelSdkResult {

opentelemetry-sdk/src/logs/log_processor_with_async_runtime.rs

@@ -317,12 +317,8 @@ mod tests {
     }
 
     impl LogExporter for MockLogExporter {
-        #[allow(clippy::manual_async_fn)]
-        fn export(
-            &self,
-            _batch: LogBatch<'_>,
-        ) -> impl std::future::Future<Output = OTelSdkResult> + Send {
-            async { Ok(()) }
+        async fn export(&self, _batch: LogBatch<'_>) -> OTelSdkResult {
+            Ok(())
         }
 
         fn shutdown(&mut self) -> OTelSdkResult {

opentelemetry-sdk/src/logs/simple_log_processor.rs

@@ -168,20 +168,14 @@ mod tests {
     }
 
     impl LogExporter for LogExporterThatRequiresTokio {
-        #[allow(clippy::manual_async_fn)]
-        fn export(
-            &self,
-            batch: LogBatch<'_>,
-        ) -> impl std::future::Future<Output = OTelSdkResult> + Send {
+        async fn export(&self, batch: LogBatch<'_>) -> OTelSdkResult {
             // Simulate minimal dependency on tokio by sleeping asynchronously for a short duration
-            async move {
-                tokio::time::sleep(Duration::from_millis(50)).await;
+            tokio::time::sleep(Duration::from_millis(50)).await;
 
-                for _ in batch.iter() {
-                    self.export_count.fetch_add(1, Ordering::Acquire);
-                }
-                Ok(())
+            for _ in batch.iter() {
+                self.export_count.fetch_add(1, Ordering::Acquire);
             }
+            Ok(())
         }
     }