Fixing EventProcessor.Checkpoint span duration (Azure#48672)

* Added an await so the OTel span matches function duration + catch is also checked.

* Updating changelog

Author: jeo02

sdk/eventhub/Azure.Messaging.EventHubs.Processor/CHANGELOG.md

@@ -8,6 +8,9 @@
 
 ### Bugs Fixed
 
+- UpdateCheckpointAsync in the 'EventProcessorClient` was not awaiting the Checkpoint Stores 'UpdateCheckpointAsync' method.
+By not awaiting we were starting the OTel span and closing it almost immediately. The catch would've been ignored as well.
+
 ### Other Changes
 
 ## 5.12.0-beta.2 (2025-02-11)

sdk/eventhub/Azure.Messaging.EventHubs.Processor/src/EventProcessorClient.cs

@@ -963,7 +963,7 @@ protected override Task UpdateCheckpointAsync(string partitionId,
         /// <param name="startingPosition">The starting position to associate with the checkpoint, indicating that a processor should begin reading from the next event in the stream.</param>
         /// <param name="cancellationToken">A <see cref="CancellationToken" /> instance to signal a request to cancel the operation.</param>
         ///
-        protected override Task UpdateCheckpointAsync(string partitionId,
+        protected override async Task UpdateCheckpointAsync(string partitionId,
                                                       CheckpointPosition startingPosition,
                                                       CancellationToken cancellationToken)
         {
@@ -989,7 +989,7 @@ protected override Task UpdateCheckpointAsync(string partitionId,
 
             try
             {
-                return CheckpointStore.UpdateCheckpointAsync(FullyQualifiedNamespace, EventHubName, ConsumerGroup, partitionId, Identifier, startingPosition, cancellationToken);
+                await CheckpointStore.UpdateCheckpointAsync(FullyQualifiedNamespace, EventHubName, ConsumerGroup, partitionId, Identifier, startingPosition, cancellationToken).ConfigureAwait(false);
             }
             catch (Exception ex)
             {