Update .travis.yml

ytake · ytake · commit b59b895a8da9 · 2019-11-17T15:38:04.000+09:00
diff --git a/.travis.yml b/.travis.yml
@@ -3,6 +3,8 @@ language: generic
 services:
 - docker
 env:
+  global:
+  - DOCKER_COMPOSE_VERSION=1.24.1
   matrix:
   - HHVM_VERSION=4.25.1
   - HHVM_VERSION=4.26.1
