Fix app healthcheck: use /proc/1/cmdline instead of pgrep

docker-compose.yml

@@ -18,7 +18,7 @@ services:
       - tckdev_net
     restart: unless-stopped
     healthcheck:
-      test: ["CMD-SHELL", "pgrep -f php-fpm > /dev/null 2>&1 || exit 1"]
+      test: ["CMD-SHELL", "grep -q php-fpm /proc/1/cmdline || exit 1"]
       interval: 10s
       timeout: 5s
       retries: 3