[MINOR] Changed guava version to 19.0 for selenium test

[jongyoul]

What is this PR for?

Enable selenium test with SafariDriver.

What type of PR is it?

[Bug Fix]

Todos

• - Upgrade guava version

What is the Jira issue?

N/A

How should this be tested?

1. Install selenium driver for Safari
2. Make sure that you don't have firefox installed
3. Start Zeppelin without this patch
4. run a selenium test. TEST_SELENIUM="true" mvn package -DfailIfNoTests=false -pl 'zeppelin-interpreter,zeppelin-zengine,zeppelin-server' -Dtest=ParagraphActionsIT
5. Got error
6. Repeat after patch
7. Success

Screenshots (if appropriate)

Got error like:

java.lang.NoSuchMethodError: com.google.common.util.concurrent.MoreExecutors.directExecutor()Ljava/util/concurrent/Executor;
    at org.openqa.selenium.safari.WebSocketConnection.send(WebSocketConnection.java:139)
    at org.openqa.selenium.safari.SafariDriverCommandExecutor.execute(SafariDriverCommandExecutor.java:188)
    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:620)
    at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:247)
    at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:129)
    at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:142)
    at org.openqa.selenium.safari.SafariDriver.<init>(SafariDriver.java:62)
    at org.openqa.selenium.safari.SafariDriver.<init>(SafariDriver.java:42)
    at org.apache.zeppelin.WebDriverManager.getWebDriver(WebDriverManager.java:103)
    at org.apache.zeppelin.integration.ParagraphActionsIT.startUp(ParagraphActionsIT.java:51)

Questions:

• Does the licenses files need update? No
• Is there breaking changes for older versions? No
• Does this needs documentation? No