[Messaging] AMQP Transport Library Version Bump (#50148)

Bumping the central version of Microsoft.Azure.Amqp
to 2.6.11 to adopt the latest fixes.  See:
https://github.com/Azure/azure-amqp/commits/hotfix/

Author: jsquire

eng/Packages.Data.props

@@ -166,7 +166,7 @@
     <PackageReference Update="Microsoft.Bcl.Numerics" Version="8.0.0" />
 
     <!-- Other approved packages -->
-    <PackageReference Update="Microsoft.Azure.Amqp" Version="2.6.9" />
+    <PackageReference Update="Microsoft.Azure.Amqp" Version="2.6.11" />
     <PackageReference Update="Microsoft.Azure.WebPubSub.Common" Version="1.4.0" />
     <PackageReference Update="Microsoft.Identity.Client" Version="4.71.1" />
     <PackageReference Update="Microsoft.Identity.Client.Extensions.Msal" Version="4.71.1" />
@@ -209,7 +209,6 @@
     <PackageReference Update="Microsoft.TypeSpec.Generator.ClientModel" Version="[$(UnbrandedGeneratorVersion)]" />
     <PackageReference Update="Microsoft.TypeSpec.Generator.Input" Version="[$(UnbrandedGeneratorVersion)]" />
     <PackageReference Update="Azure.Generator" Version="[$(AzureGeneratorVersion)]" />
-    <PackageReference Update="System.ClientModel" Version="1.4.1" />
   </ItemGroup>
 
   <!--

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

@@ -12,6 +12,8 @@
 
 ### Other Changes
 
+- Updated the `Microsoft.Azure.Amqp` dependency to 2.6.11, which contains several bug fixes. _(see: [commits](https://github.com/Azure/azure-amqp/commits/hotfix/))_
+
 ## 5.12.1 (2025-04-09)
 
 ### Bugs Fixed

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

@@ -18,7 +18,9 @@ Thank you to our developer community members who helped to make the Event Hubs c
 
 ### Other Changes
 
-- Significantly improved the performance of the Jenkins3 hash computation used for partition key resolution. Across various input sizes, the updated implementation achieves up to 39% faster hash calculation, with the most notable gains seen for smaller keys (8–32 bytes), and consistent improvements across all sizes. The new approach maintains the exact bit-for-bit hash output while reducing overhead.  _(A community contribution, courtesy of [danielmarbach](https://github.com/danielmarbach))_
+- Updated the `Microsoft.Azure.Amqp` dependency to 2.6.11, which contains several bug fixes. _(see: [commits](https://github.com/Azure/azure-amqp/commits/hotfix/))_
+
+- Improved the performance of the Jenkins3 hash computation used for partition key resolution. Across various input sizes, the updated implementation achieves up to 39% faster hash calculation, with the most notable gains seen for smaller keys (8–32 bytes), and consistent improvements across all sizes. The new approach maintains the exact bit-for-bit hash output while reducing overhead.  _(A community contribution, courtesy of [danielmarbach](https://github.com/danielmarbach))_
 
 ## 5.12.1 (2025-04-09)
 

sdk/eventhub/Microsoft.Azure.WebJobs.Extensions.EventHubs/CHANGELOG.md

@@ -12,6 +12,8 @@
 
 ### Other Changes
 
+- Updated the `Microsoft.Azure.Amqp` dependency to 2.6.11, which contains several bug fixes. _(see: [commits](https://github.com/Azure/azure-amqp/commits/hotfix/))_
+
 ## 6.5.1 (2025-04-09)
 
 ### Bugs Fixed

sdk/servicebus/Azure.Messaging.ServiceBus/CHANGELOG.md

@@ -24,6 +24,8 @@
 
 - Enhanced retry logic to consider additional cases for web socket-based failures.  In many cases, a `WebSocketException` is triggered which wraps a `SocketException` with the details for the specific network conditions.  Retry decisions are now based on the internal exception, if present, to ensure retries are correctly applied.
 
+- Updated the `Microsoft.Azure.Amqp` dependency to 2.6.11, which contains several bug fixes. _(see: [commits](https://github.com/Azure/azure-amqp/commits/hotfix/))_
+
 ## 7.18.4 (2025-02-11)
 
 ### Bugs Fixed

sdk/servicebus/Microsoft.Azure.WebJobs.Extensions.ServiceBus/CHANGELOG.md

@@ -10,6 +10,8 @@
 
 ### Other Changes
 
+- Updated the `Microsoft.Azure.Amqp` dependency to 2.6.11, which contains several bug fixes. _(see: [commits](https://github.com/Azure/azure-amqp/commits/hotfix/))_
+
 ## 5.16.6 (2025-04-08)
 
 ### Other Changes