Migrate from Travis CI to GitHub Actions

.github/workflows/passbook.yml

@@ -0,0 +1,31 @@
+# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-python
+
+name: Passbook
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: [3.8]
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v4
+      with:
+        python-version: ${{ matrix.python-version }}
+        cache: 'pip'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install -r requirements_test.txt
+    - name: Test with pytest
+      run: |
+        py.test

README.md

@@ -1,6 +1,6 @@
 # Passbook
 
-[![Build Status](https://travis-ci.org/devartis/passbook.svg?branch=master)](https://travis-ci.org/devartis/passbook)
+[![Build Status](https://github.com/devartis/passbook/actions/workflows/passbook.yml/badge.svg)](https://github.com/devartis/passbook/actions)
 
 Python library to create Apple Wallet (.pkpass) files (Apple Wallet 
 has previously been known as Passbook in iOS 6 to iOS 8).

requirements.txt

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+# GitHub Actions requires a file "requirements.txt" or "pyproject.toml".