tag image via action workflow

.github/workflows/main.yml

@@ -38,6 +38,7 @@ jobs:
       - name: Build (latest)
         if: ${{ github.ref == 'refs/heads/main' }}
         run: |
+          export TAG=amd64
           export VCS_REF=$(git rev-parse HEAD)
           npm install -g @devcontainers/cli
           devcontainer build --workspace-folder . --config devcontainer.json --image-name cs50/codespace:${{ github.sha }} --image-name cs50/codespace:latest
@@ -59,6 +60,7 @@ jobs:
       - name: Build ${{ github.ref_name}}
         if: ${{ github.ref != 'refs/heads/main' }}
         run: |
+          export TAG=amd64
           export VCS_REF=$(git rev-parse HEAD)
           npm install -g @devcontainers/cli
           devcontainer build --workspace-folder . --config devcontainer.json --image-name cs50/codespace:${{ github.sha }} --image-name cs50/codespace:${{ github.ref_name }}

Dockerfile

@@ -1,5 +1,5 @@
 # Build stage
-ARG TAG=amd64
+ARG TAG
 FROM cs50/cli:${TAG} as builder
 ARG DEBIAN_FRONTEND=noninteractive
 

devcontainer.json

@@ -1,6 +1,7 @@
 {
     "build": {
         "args": {
+            "TAG": "${localEnv:TAG}",
             "VCS_REF": "${localEnv:VCS_REF}"
         },
         "context": ".",