chore(deps): update dotnet monorepo to v9

Dockerfile

@@ -1,9 +1,9 @@
-FROM mcr.microsoft.com/dotnet/aspnet:7.0 AS base
+FROM mcr.microsoft.com/dotnet/aspnet:9.0 AS base
 WORKDIR /app
 EXPOSE 80
 EXPOSE 443
 
-FROM mcr.microsoft.com/dotnet/sdk:7.0 AS build
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build
 WORKDIR /source
 
 # copy csproj and restore as distinct layers
@@ -16,7 +16,7 @@ RUN dotnet publish -o /app
 
 
 # final stage/image
-FROM mcr.microsoft.com/dotnet/aspnet:7.0
+FROM mcr.microsoft.com/dotnet/aspnet:9.0
 WORKDIR /app
 COPY --from=build /app .
 ENTRYPOINT ["./Server"]