Downgraded Microsoft.SemanticKernel.Abstractions to resolve image file upload issue.

Author: Prasanjeet-Microsoft

App/kernel-memory/Directory.Packages.props

@@ -66,7 +66,7 @@
   <!-- Semantic Kernel -->
   <ItemGroup>
     <PackageVersion Include="Microsoft.SemanticKernel" Version="1.15.1" />
-    <PackageVersion Include="Microsoft.SemanticKernel.Abstractions" Version="1.31.0" />
+    <PackageVersion Include="Microsoft.SemanticKernel.Abstractions" Version="1.15.1" />
     <PackageVersion Include="Microsoft.SemanticKernel.Connectors.OpenAI" Version="1.15.1" />
   </ItemGroup>
   <!-- Documentation -->