Replace Azure Pipelines with GitHub Actions

Author: KodrAus

.github/workflows/rust.yml

@@ -0,0 +1,33 @@
+name: Continuous integration
+
+on:
+  pull_request:
+  push:
+      branches:
+      - master
+
+jobs:
+  os_tests:
+    name: "Tests / OS: ${{ matrix.os }} - ${{ matrix.channel }}"
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        channel:
+        - stable
+        - beta
+        - nightly
+        - 1.23.0
+        os:
+        - macos-10.15
+        - windows-2019
+        - ubuntu-20.04
+  
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    - name: Update rust
+      run: rustup update ${{ matrix.channel }} --no-self-update
+
+    - name: Tests
+      run: cargo +${{ matrix.channel }} test --all