this looks like defiantly something to do with driver version mismatch.
you have to do lot of different test as I don't know your configuration. I also spend almost two days testing out different combination and searching on internet and then configuration that I posted work.
this one was the key
jdbc_driver_class => "com.microsoft.sqlserver.jdbc.SQLServerDriver"
Curretnly i have
ls -la /usr/share/logstash/logstash-core/lib/jars/mssql-jdbc-7.4.1.jre8.jar
-rw-r--r-- 1 logstash logstash 1209659 Sep 17 2019 /usr/share/logstash/logstash-core/lib/jars/mssql-jdbc-7.4.1.jre8.jar