Upgrade travis-utils to version 55

travis.sh

@@ -8,7 +8,7 @@ set -euo pipefail
 #
 configureTravis() {
   mkdir -p ~/.local
-  curl -sSL https://github.com/SonarSource/travis-utils/tarball/v50 | tar zx --strip-components 1 -C ~/.local
+  curl -sSL https://github.com/SonarSource/travis-utils/tarball/v55 | tar zx --strip-components 1 -C ~/.local
   source ~/.local/bin/install
 }
 configureTravis