Try to fix travis

Old URL returns 404, picked new from official webpage: https://kafka.apache.org/downloads

Author: filimonov

.travis.yml

@@ -23,7 +23,7 @@ addons:
 
 before_script:
   - KAFKA_VERSION=2.11-2.2.0
-  - wget http://apache.cs.utah.edu/kafka/2.2.0/kafka_$KAFKA_VERSION.tgz
+  - wget https://archive.apache.org/dist/kafka/2.2.0/kafka_$KAFKA_VERSION.tgz
   - tar xvzf kafka_$KAFKA_VERSION.tgz
   - ./kafka_$KAFKA_VERSION/bin/kafka-server-start.sh ./kafka_$KAFKA_VERSION/config/server.properties > /dev/null 2> /dev/null &
   - git clone https://github.com/edenhill/librdkafka.git