bump the used proxy version to one that includes the optimizations and fixes necessary to enable the java openai tests (#43203)

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

Author: azure-sdk

eng/common/testproxy/target_version.txt

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