Update dotnet-6.0.Dockerfile

dockerfiles/dotnet-6.0.Dockerfile

@@ -4,15 +4,17 @@ COPY codecrafters-redis.csproj /app/codecrafters-redis.csproj
 COPY codecrafters-redis.sln /app/codecrafters-redis.sln
 
 RUN mkdir /app/src
-RUN echo 'System.Console.WriteLine("Hello World 2!");' > /app/src/Program.cs
+RUN echo 'System.Console.WriteLine("If you are seeing this, there is something wrong with our caching mechanism! Please contact us at hello@codecrafters.io.");' > /app/src/Program.cs
 
 WORKDIR /app
 
 RUN dotnet run --project . --configuration Release "$@" # This saves nuget packages to ~/.nuget
+RUN rm /app/src/Program.cs
 
-RUN mkdir /app-cached
-RUN mv /app/obj /app-cached/obj
-RUN mv /app/bin /app-cached/bin
+# This seems to cause a caching issue with the dotnet build command, where contents from the removed /src/Program.cs are used
+# RUN mkdir /app-cached
+# RUN mv /app/obj /app-cached/obj
+# RUN mv /app/bin /app-cached/bin
 
 RUN echo "cd \${CODECRAFTERS_SUBMISSION_DIR} && dotnet build --configuration Release ." > /codecrafters-precompile.sh
 RUN chmod +x /codecrafters-precompile.sh