Update chillicream-gql to 15.1.8

Author: renovate[bot]

.config/dotnet-tools.json

@@ -48,7 +48,7 @@
             "rollForward": false
         },
         "strawberryshake.tools": {
-            "version": "15.0.3",
+            "version": "15.1.8",
             "commands": ["dotnet-graphql"],
             "rollForward": false
         },

Directory.Packages.props

@@ -30,7 +30,7 @@
         <PackageVersion Include="Rocket.Surgery.LaunchPad.Foundation" Version="1.8.8" />
         <PackageVersion Include="Polyfill" Version="8.7.4" />
         <PackageVersion Include="Spectre.Console.Cli" Version="0.49.1" />
-        <PackageVersion Include="StrawberryShake.Server" Version="15.0.3" />
+        <PackageVersion Include="StrawberryShake.Server" Version="15.1.8" />
         <PackageVersion Include="Verify.BUnit" Version="12.0.0" />
         <PackageVersion Include="Xunit.SkippableFact" Version="1.5.23" />
         <PackageVersion Include="YamlDotNet" Version="16.3.0" />