forgot to add image

docker-compose.yml

@@ -1,7 +1,7 @@
 ---
 services:
   runner:
-    image:
+    image: docker.io/gitea/act_runner:${ACT_VERSION}
     environment:
       - CONFIG_FILE=/config.yaml
       - GITEA_INSTANCE_URL="${GITEA_URL}"

env.example

@@ -1,4 +1,5 @@
 # Gitea Act Runner
+ACT_VERSION=latest
 ACT_DATA=./data
 GITEA_URL=https://git.example.com
 GITEA_TOKEN=abc123