add ci tests

Author: MarvinSchramm

.github/workflows/tests.yml

@@ -0,0 +1,39 @@
+name: Tests
+
+# Controls when the action will run.
+on:
+
+  pull_request:
+    branches: [ main ]
+
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+# A workflow run is made up of one or more jobs that can run sequentially or in parallel
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Git Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Setup Java
+        uses: actions/setup-java@v1
+        with:
+          java-version: '15'
+
+      - name: Setup Build Cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+      - name: Tests
+        run: |
+          ./gradlew check