Revert "Revert "Upgrade to .NET 9""

This reverts commit a225c18.

Author: tumugin

.github/workflows/test-migration.yaml

@@ -29,7 +29,7 @@ jobs:
           --health-retries 5
     steps:
       - uses: actions/checkout@v4
-      - name: Setup .NET Core SDK 7.0
+      - name: Setup .NET SDK
         uses: actions/setup-dotnet@v4
         with:
           global-json-file: global.json

.github/workflows/test.yaml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - name: Setup .NET Core SDK 7.0
+      - name: Setup .NET SDK
         uses: actions/setup-dotnet@v4
         with:
           global-json-file: global.json

Dockerfile

@@ -1,5 +1,5 @@
 # see: https://hub.docker.com/_/microsoft-dotnet-sdk/
-FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build-env
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build-env
 
 WORKDIR /App
 
@@ -30,7 +30,7 @@ RUN dotnet publish -c Release -o out
 
 # Build runtime image
 # see: https://hub.docker.com/_/microsoft-dotnet-aspnet/
-FROM mcr.microsoft.com/dotnet/aspnet:8.0
+FROM mcr.microsoft.com/dotnet/aspnet:9.0
 
 WORKDIR /App/Lullaby
 COPY --from=build-env /App/Lullaby/out .

global.json

@@ -1,7 +1,7 @@
 {
   "sdk": {
-    "version": "8.0.403",
+    "version": "9.0.100",
     "rollForward": "feature",
     "allowPrerelease": true
   }
-}
+}