Fix the generate_tests.sh to actually be executable.

.travis.yml

@@ -12,7 +12,7 @@ install:
   - docker-compose --version
 
 before_script:
-  - tests/generate_tests.sh
+  - sh tests/generate_tests.sh
   - docker-compose -f docker-compose.yaml -f docker-test.yaml up -d
   - docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' mailman-core
   - docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' mailman-web

tests/generate_tests.sh

@@ -1,3 +1,5 @@
+#!/bin/sh
+
 if [ "$TRAVIS_BRANCH" = "master" ]; then
     TAG="latest"
 else