Release workflow

.github/workflows/constraints.txt

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+pip==20.1.1
+nox==2020.5.24
+poetry==1.0.9
+pre-commit==2.5.1

.github/workflows/release.yml

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+name: Release
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  release:
+    name: Release
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out the repository
+        uses: actions/checkout@v2.1.1
+        with:
+          fetch-depth: 2
+
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: "3.8"
+
+      - name: Upgrade pip
+        run: |
+          pip install --constraint=.github/workflows/constraints.txt pip
+          pip --version
+
+      - name: Install Poetry
+        run: |
+          pip install --constraint=.github/workflows/constraints.txt poetry
+          poetry --version
+
+      - name: Check if there is a parent commit
+        id: check-parent-commit
+        run: |
+          echo "::set-output name=sha::$(git rev-parse --verify --quiet HEAD^)"
+
+      - name: Detect and tag new version
+        id: check-version
+        if: steps.check-parent-commit.outputs.sha
+        uses: salsify/action-detect-and-tag-new-version@v1.0.3
+        with:
+          version-command: |
+            poetry version | awk '{ print $2 }'
+
+      - name: Bump version for developmental release
+        if: "! steps.check-version.outputs.tag"
+        run: |
+          poetry version patch &&
+          version=$(poetry version | awk '{ print $2 }') &&
+          poetry version $version.dev.$(date +%s)
+
+      - name: Publish the release notes
+        uses: release-drafter/release-drafter@v5.11.0
+        with:
+          publish: ${{ steps.check-version.outputs.tag != '' }}
+          tag: ${{ steps.check-version.outputs.tag }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}