Merge pull request #61949 from aireilly/fix-travis

add rouge

Author: gabriel-rh

.travis.yml

@@ -15,6 +15,7 @@ jobs:
       install:
         - gem install asciidoctor
         - gem install asciidoctor-diagram
+        - gem install rouge
       script:
         - chmod +x ./scripts/check-asciidoctor-build.sh
         - ./scripts/check-asciidoctor-build.sh