Sync eng/common directory with azure-sdk-tools for PR 12293 (Azure#52955)

* bump the used proxy version to one that includes the optimizations and fixes necessary to enable the java openai tests
* bump version in packages.data.props to align with target_version.txt

---------

Co-authored-by: Scott Beddall <[email protected]>

Author: azure-sdk

eng/Packages.Data.props

@@ -466,7 +466,7 @@
   </ItemGroup>
 
   <PropertyGroup>
-    <TestProxyVersion>1.0.0-dev.20250922.2</TestProxyVersion>
+    <TestProxyVersion>1.0.0-dev.20250930.1</TestProxyVersion>
     <UnbrandedGeneratorVersion>1.0.0-alpha.20250929.3</UnbrandedGeneratorVersion>
     <AzureGeneratorVersion>1.0.0-alpha.20250929.3</AzureGeneratorVersion>
   </PropertyGroup>

eng/common/testproxy/target_version.txt

@@ -1 +1 @@
-1.0.0-dev.20250922.2
+1.0.0-dev.20250930.1