Added automated smoketest

docker-compose.test.yml

@@ -0,0 +1,11 @@
+version: '3.5'
+services:
+  app:
+    build: .
+  sut:
+    image: alpine:3.10
+    depends_on:
+      - app
+    command: /tmp/run_tests.sh
+    volumes:
+      - "./run_tests.sh:/tmp/run_tests.sh:ro"

run_tests.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env sh
+apk --no-cache add curl
+curl --silent --fail http://app:8080 | grep 'PHP 7.3'