chore(deps): point to ubuntu base image

.devcontainer/Dockerfile

@@ -1,10 +1,9 @@
 # See here for image contents: https://github.com/microsoft/vscode-dev-containers/tree/v0.233.0/containers/ubuntu/.devcontainer/base.Dockerfile
 
 # [Choice] Ubuntu version (use ubuntu-22.04 or ubuntu-18.04 on local arm64/Apple Silicon): ubuntu-22.04, ubuntu-20.04, ubuntu-18.04
-ARG VARIANT="jammy"
 #https://mcr.microsoft.com/v2/devcontainers/base/tags/list
 #https://github.com/devcontainers/images/tree/main/src/base-ubuntu
-FROM mcr.microsoft.com/vscode/devcontainers/base:0-${VARIANT}
+FROM mcr.microsoft.com/vscode/devcontainers/base:0-ubuntu-22.04
 
 # [Optional] Uncomment this section to install additional OS packages.
 # RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \