Adjust release workflow

Author: jwodder

.github/workflows/release.yml

@@ -10,8 +10,6 @@ jobs:
   auto-release:
     runs-on: ubuntu-latest
     if: "!contains(github.event.head_commit.message, 'ci skip') && !contains(github.event.head_commit.message, 'skip ci')"
-    outputs:
-      auto-version: ${{ steps.auto-version.outputs.version }}
     steps:
       - name: Checkout source
         uses: actions/checkout@v2
@@ -26,14 +24,6 @@ jobs:
           wget -O- https://github.com/intuit/auto/releases/download/v10.16.1/auto-linux.gz | gunzip > ~/auto
           chmod a+x ~/auto
 
-      - name: Set up Python
-        uses: actions/setup-python@v2
-        with:
-          python-version: '^3.7'
-
-      - name: Install Python dependencies
-        run: python -m pip install build bump2version twine
-
       - name: Check whether a release is due
         id: auto-version
         run: |
@@ -42,42 +32,40 @@ jobs:
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Set up Python
+        if: steps.auto-version.outputs.version != ''
+        uses: actions/setup-python@v2
+        with:
+          python-version: '^3.7'
+
+      - name: Install Python dependencies
+        if: steps.auto-version.outputs.version != ''
+        run: python -m pip install build bump2version twine
+
       - name: Create release
+        if: steps.auto-version.outputs.version != ''
         run: ~/auto shipit
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           TWINE_USERNAME: __token__
           TWINE_PASSWORD: ${{ secrets.PYPI_TOKEN }}
 
-  build-docker:
-    runs-on: ubuntu-latest
-    needs: auto-release
-    if: needs.auto-release.outputs.auto-version != ''
-    steps:
-      - name: Get tag of latest release
-        id: latest-release
-        run: |
-          latest_tag="$(curl -fsSL https://api.github.com/repos/$GITHUB_REPOSITORY/releases/latest | jq -r .tag_name)"
-          echo "::set-output name=tag::$latest_tag"
-
-      - name: Checkout source
-        uses: actions/checkout@v2
-        with:
-          ref: ${{ steps.latest-release.outputs.tag }}
-
       - name: Generate Dockerfile
+        if: steps.auto-version.outputs.version != ''
         run: bash gen-docker-image.sh
         working-directory: utils
 
       - name: Build Docker images
+        if: steps.auto-version.outputs.version != ''
         run: |
           docker build \
             -t nipy/heudiconv:master \
             -t nipy/heudiconv:latest \
-            -t nipy/heudiconv:${{ steps.latest-release.outputs.tag }} \
+            -t nipy/heudiconv:"$(git describe)" \
             .
 
       - name: Push Docker images
+        if: steps.auto-version.outputs.version != ''
         run: |
           docker login -u "$DOCKER_LOGIN" --password-stdin <<<"$DOCKER_TOKEN"
           docker push --all-tags nipy/heudiconv