feat(travis): cleanup before_script

Author: KaiSchwarz-cnic

.travis.yml

@@ -15,8 +15,6 @@ before_install:
   - if [[ "$TRAVIS_BRANCH" == "master" && "$TRAVIS_PULL_REQUEST" == "false" ]]; then
       openssl aes-256-cbc -K $encrypted_c9f9aedf26b7_key -iv $encrypted_c9f9aedf26b7_iv -in codesigning.asc.enc -out codesigning.asc -d &&
       gpg --import --batch codesigning.asc ; fi
-before_script:
-  - yarn global add @conveyal/maven-semantic-release semantic-release
 script:
   - mvn package
 after_success: