Add automatic multi-architecture Docker builds (#2274)

We currently only release `amd64` images. Some users may want to run on
`arm64` platforms provided by various cloud providers, and developers
may operate from arm64-based Macs. This PR adds multi-architecture
builds to our automated release process.

.github/workflows/build-latest-images.yml

@@ -20,6 +20,7 @@ jobs:
  name: Build standard production image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash:latest"
  target: cdash
@@ -39,6 +40,7 @@ jobs:
  name: Build UBI production image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash:latest-ubi"
  target: cdash
@@ -60,6 +62,7 @@ jobs:
  name: Build standard worker image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash-worker:latest"
  target: cdash-worker
@@ -79,6 +82,7 @@ jobs:
  name: Build UBI worker image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash-worker:latest-ubi"
  target: cdash-worker
@@ -100,6 +104,7 @@ jobs:
  name: Build standard development image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash:testing"
  target: cdash
@@ -121,6 +126,7 @@ jobs:
  name: Build UBI development image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash:testing-ubi"
  target: cdash

.github/workflows/release.yml

@@ -19,6 +19,7 @@ jobs:
  name: Build ${{ github.ref_name }} image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash:${{ github.ref_name }}"
  target: cdash
@@ -28,6 +29,7 @@ jobs:
  name: Build ${{ github.ref_name }} worker image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash-worker:${{ github.ref_name }}"
  target: cdash-worker
@@ -47,6 +49,7 @@ jobs:
  name: Build ${{ github.ref_name }} image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash:${{ github.ref_name }}-ubi"
  target: cdash
@@ -58,6 +61,7 @@ jobs:
  name: Build ${{ github.ref_name }} worker image
  with:
  context: .
+ platforms: linux/amd64,linux/arm64
  push: true
  tags: "kitware/cdash-worker:${{ github.ref_name }}-ubi"
  target: cdash-worker