chore(deps): update dependency microsoft.azure.functions.worker.core to v1.15.0

Author: renovate[bot]

src/Octokit.Webhooks.AzureFunctions/Octokit.Webhooks.AzureFunctions.csproj

@@ -19,7 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Azure.Functions.Worker.Core" Version="1.14.0" />
+    <PackageReference Include="Microsoft.Azure.Functions.Worker.Core" Version="1.15.0" />
     <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Abstractions" Version="1.3.0" />
     <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.0.13" />
   </ItemGroup>