Run style checks using GitHub Actions instead of Azure Pipelines (#519)

* Run style checks using GitHub Actions
* Remove Azure Pipelines
* Update Continuous Integration maintenance note to include GH Actions

Co-authored-by: Wei Ji <[email protected]>

Author: seisman

.azure-pipelines.yml

@@ -12,6 +12,30 @@ on:
     - cron: '0 0 * * *'
 
 jobs:
+  style_check:
+    name: Style Checks
+    runs-on: ubuntu-latest
+
+    steps:
+      # Checkout current git repository
+      - name: Checkout
+        uses: actions/[email protected]
+
+      # Setup Miniconda
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.7
+
+      - name: Install packages
+        run: pip install black flake8 pylint
+
+      - name: Formatting check (black and flake8)
+        run: make check
+
+      - name: Linting (pylint)
+        run: make lint
+
   test:
     name: ${{ matrix.os }} - Python ${{ matrix.python-version }}
     runs-on: ${{ matrix.os }}

.github/workflows/ci_tests.yaml

@@ -40,10 +40,11 @@ The main advantages of this are:
 
 ## Continuous Integration
 
-We use TravisCI continuous integration (CI) services to build and test the
-project on Linux, and Mac (Windows is still a work in progress).
-The configuration file for this service is `.travis.yml`.
-It relies on the `requirements.txt` file to install the required dependencies using
+We use Github Actions and TravisCI continuous integration (CI) services to
+build and test the project on Linux, macOS and Windows.
+The configuration file for these services are in
+`.github/workflows/ci_tests.yaml` and `.travis.yml`.
+They rely on the `requirements.txt` file to install required dependencies using
 conda and the `Makefile` to run the tests and checks.
 
 Travis also handles all of our deployments automatically:

MAINTENANCE.md

@@ -12,9 +12,6 @@ PyGMT
 .. image:: http://img.shields.io/travis/GenericMappingTools/pygmt/master.svg?style=flat-square&label=Linux
     :alt: Travis CI build status
     :target: https://travis-ci.org/GenericMappingTools/pygmt
-.. image:: https://img.shields.io/azure-devops/build/GenericMappingTools/7682ad4e-76bb-4775-849e-7c4f8dce4e1a/3/master.svg?label=Mac|Windows&style=flat-square
-    :alt: Azure Pipelines build status
-    :target: https://dev.azure.com/GenericMappingTools/PyGMT/_build
 .. image:: https://github.com/GenericMappingTools/pygmt/workflows/Tests/badge.svg
     :alt: GitHub Actions build status
     :target: https://github.com/GenericMappingTools/pygmt/actions