Add CI workflow for tests and build

.github/workflows/tests.yml

@@ -0,0 +1,38 @@
+name: Tests
+run-name: "Build, tests and package"
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    paths-ignore:
+      - '**.md'
+
+jobs:
+  build:
+    strategy:
+      matrix:
+        os: [ 'ubuntu-latest', 'macos-latest' ]
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v3
+      - name: Set up JDK 1.8
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: '8'
+          cache: maven
+
+      # Need to downgrade Maven in order to allow HTTP (not HTTPS) packages to be downloaded.
+      # This is necessary as HTTP repositories were blocked in Maven 3.8.1
+      # HTTP repositories are used in some outdated dependenciesns
+      # This step can be removed once KLASS packages have been updated to more recent versions
+      - name: Set up Maven
+        uses: stCarolas/setup-maven@v4.5
+        with:
+          maven-version: 3.6.3
+
+      - name: Build, test and package with Maven
+        run: mvn --batch-mode --update-snapshots package -P nexus