Update Dockerfile

 hanged Variant to latest version 8.0 dotnet

.devcontainer/Dockerfile

@@ -1,6 +1,6 @@
 # [Choice] .NET version: 7.0, 6.0, 3.1, 6.0-bullseye, 3.1-bullseye, 6.0-focal, 3.1-focal
 # See here for devcontainer tags: https://mcr.microsoft.com/v2/devcontainers/dotnet/tags/list
-ARG VARIANT="7.0-jammy"
+ARG VARIANT="8.0-jammy"
 FROM mcr.microsoft.com/vscode/devcontainers/dotnet:${VARIANT}
 
 # [Choice] Node.js version: none, lts/*, 18, 16, 14
@@ -13,4 +13,4 @@ RUN export DEBIAN_FRONTEND=noninteractive \
     && apt-get clean -y
 
 # [Optional] Uncomment this line to install global node packages.
-# RUN su vscode -c "source /usr/local/share/nvm/nvm.sh && npm install -g <your-package-here>" 2>&1
+# RUN su vscode -c "source /usr/local/share/nvm/nvm.sh && npm install -g <your-package-here>" 2>&1