CVE-2020-13955: Improper Certificate Validation

HttpUtils#getURLConnection method disables explicitly hostname verification for HTTPS connections making clients vulnerable to man-in-the-middle attacks. Calcite uses internally this method to connect with Druid and Splunk so information leakage may happen when using the respective Calcite adapters. The method itself is in a utility class so people may use it to create vulnerable HTTPS connections for other applications. From Apache Calcite 1.26 onwards, the hostname verification will be performed using the default JVM truststore.