Migrate deprecated Travis CI settings

Author: Atry

.travis.yml

@@ -1,5 +1,3 @@
-sudo: false
-
 addons:
  apt:
    packages:
@@ -31,7 +29,7 @@ before_deploy:
 deploy:
   - provider: script
     script: sbt ++$TRAVIS_SCALA_VERSION "set every Seq(sonatypeSessionName := \"Travis Job $TRAVIS_JOB_NAME $TRAVIS_JOB_NUMBER ($TRAVIS_JOB_WEB_URL)\", publishTo := sonatypePublishToBundle.value)" publishSigned sonatypeBundleRelease
-    skip_cleanup: true
+    cleanup: false
     on:
       all_branches: true
       condition: $GITHUB_PERSONAL_ACCESS_TOKEN