Add an initial version to github actions ci

.github/workflows/ci.yml

@@ -0,0 +1,23 @@
+name: Build and Test
+on: [push, pull_request]
+jobs:
+  ubuntu:
+    strategy:
+      matrix:
+        version: ["7.2", "7.3", "7.4", "8.0", "8.1", "8.2"]
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout pdlib
+        uses: actions/checkout@v3
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{matrix.version}}
+      - name: phpize
+        run: phpize
+      - name: configure
+        run: ./configure
+      - name: make
+        run: make
+      - name: test
+        run: make test TESTS="--show-diff tests"