Setup CI using GitHub Actions

.github/workflows/py.yml

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+name: Python CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  test:
+    runs-on: ubuntu-18.04
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python
+        uses: actions/setup-python@v1
+        with:
+          python-version: 3.7.6
+      - name: Install build tools
+        run: |
+          python -m pip install -U pip==20.0.2
+          python -m pip install -U setuptools==45.1.0
+          python -m pip install -U poetry==1.0.3
+          poetry config virtualenvs.create false
+      - name: Install dependencies
+        run: python -m poetry install
+      - name: Lint + Test (isort/black/mypy/pylint/pytest)
+        run: ./dev/test.sh

README.md

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+# Flower