Bump the dotnet group with 1 update

Bumps Microsoft.Agents.AI.OpenAI from 1.6.1 to 1.7.0

---
updated-dependencies:
- dependency-name: Microsoft.Agents.AI.OpenAI
  dependency-version: 1.7.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: dotnet
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

docs/ai/snippets/prompt-engineering/multi-turn-chat.csproj

@@ -10,7 +10,7 @@
 
   <ItemGroup>
     <PackageReference Include="Azure.AI.OpenAI" Version="2.8.0-beta.1" />
-    <PackageReference Include="Microsoft.Agents.AI.OpenAI" Version="1.6.1" />
+    <PackageReference Include="Microsoft.Agents.AI.OpenAI" Version="1.7.0" />
     <!--
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="10.0.2" />
     <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" Version="10.0.2" />