Bump test engine version

Signed-off-by: Joffrey F <[email protected]>

Author: shin-

Jenkinsfile

@@ -7,7 +7,7 @@ def images = [:]
 
 // Note: Swarm in dind seem notoriously flimsy with 1.12.1+, which is why we're
 // sticking with 1.12.0 for the 1.12 series
-def dockerVersions = ["1.12.0", "1.13.0"]
+def dockerVersions = ["1.12.0", "1.13.1"]
 
 def buildImage = { name, buildargs, pyTag ->
   img = docker.image(name)