Build using github actions

new file:   .github/workflows/main.yaml

Author: Ranjan Dasgupta

.github/workflows/main.yaml

@@ -0,0 +1,34 @@
+# Workflow to build mqtt.paho.java library 
+
+name: Java CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        # os: [ubuntu-latest, macOS-latest, windows-latest]
+        # java: [ 8.0.192, 8, 11.0.3, 17, 18-ea ]
+        os: [ubuntu-latest]
+        java: [ 11.0.3 ]
+      fail-fast: false
+      max-parallel: 4
+    name: Test MQTT Paho Java on JDK ${{ matrix.java }}, ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up JDK ${{ matrix.java }} ${{ matrix.os }}
+        uses: actions/setup-java@v1
+        with:
+          java-version: ${{ matrix.java }}
+          java-package: jdk # optional (jdk, jre, jdk+fx or jre+fx)
+      - name: Package and test with Maven
+        run: mvn package
+