diff --git a/.github/workflows/docker-image.yml b/.github/workflows/docker-image.yml
index 3df1a9ca..6ed5bcba 100644
--- a/.github/workflows/docker-image.yml
+++ b/.github/workflows/docker-image.yml
@@ -1,6 +1,7 @@
+---
 name: Docker Image CI
 
-on:
+on:  # yamllint disable-line rule:truthy
   push:
     branches: ["master"]
   pull_request: