ZOOKEEPER-3761: Upgrade JLine version to 2.14.6

Author: asutosh936 <asutosh.pandya@hotmail.com>

Reviewers: Enrico Olivelli <eolivelli@apache.org>, Mate Szalay-Beko <symat@apache.org>

Closes #1292 from asutosh936/ZOOKEEPER-3761

pom.xml

@@ -437,7 +437,7 @@
     <jetty.version>9.4.24.v20191120</jetty.version>
     <jackson.version>2.10.3</jackson.version>
     <json.version>1.1.1</json.version>
-    <jline.version>2.11</jline.version>
+    <jline.version>2.14.6</jline.version>
     <snappy.version>1.1.7</snappy.version>
     <kerby.version>2.0.0</kerby.version>
     <bouncycastle.version>1.60</bouncycastle.version>