Add CI yaml file.

.github/workflows/ci.yaml

@@ -0,0 +1,29 @@
+name: CI
+on:
+  push:
+    branches: ["main"]
+    tags: ["v*"]
+  pull_request:
+    branches: ["*"]
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - uses: actions/setup-java@v3
+        with:
+          distribution: 'temurin'
+          java-version: '17'
+          cache: 'sbt'
+
+      - name: Test
+        run: sbt --client ci
+
+      - name: Test publishing
+        run: sbt --client publishLocal