Bump Microsoft.AspNetCore.OpenApi from 8.0.14 to 8.0.19

---
updated-dependencies:
- dependency-name: Microsoft.AspNetCore.OpenApi
  dependency-version: 8.0.19
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

LLama.WebAPI/LLama.WebAPI.csproj

@@ -9,7 +9,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.VisualStudio.Validation" Version="17.8.8" />
-    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.14" />
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.19" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="7.3.1" />
   </ItemGroup>