correct the yaml syntax

Author: tingox

.github/workflows/docker-image-p2k16-label.yml

@@ -38,6 +38,7 @@ jobs:
 
       - name: Debug info
         id: debug1
-        run: echo debug github.ref = ${GITHUB_REF}
-        run: echo debug2 github.ref = ${github.ref}
+        run: |
+          echo debug github.ref = ${GITHUB_REF}
+          echo debug2 github.ref = ${github.ref}
 # so, GITHUB_REF is equal to the release tag, for example refs/tags/v0.3.0.2