Update devcontainer.json

Fixed the vscode extensions section

.devcontainer/devcontainer.json

@@ -4,21 +4,12 @@
   "name": "C# (.NET)",
   // Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
   "image": "mcr.microsoft.com/devcontainers/dotnet:1-8.0-bookworm",
+
+  // Features to add to the dev container. More info: https://containers.dev/features.
   "features": {
     "ghcr.io/devcontainers/features/powershell:1": {}
   },
 
-  // Add the IDs of extensions you want installed when the container is created.
-  "extensions": [
-    "formulahendry.dotnet-test-explorer",
-    "ms-dotnettools.csharp",
-    "ms-dotnettools.dotnet-interactive-vscode",
-    "ms-toolsai.jupyter"
-  ],
-
-  // Features to add to the dev container. More info: https://containers.dev/features.
-  // "features": {},
-
   // Use 'forwardPorts' to make a list of ports inside the container available locally.
   // "forwardPorts": [5000, 5001],
   // "portsAttributes": {
@@ -31,7 +22,16 @@
   // "postCreateCommand": "dotnet restore",
 
   // Configure tool-specific properties.
-  // "customizations": {},
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "formulahendry.dotnet-test-explorer",
+        "ms-dotnettools.csharp",
+        "ms-dotnettools.dotnet-interactive-vscode",
+        "ms-toolsai.jupyter"
+      ]
+    }
+  }
 
   // Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
   // "remoteUser": "root"