phoenix-client-embedded includes a Jetty server, and the servlet API.
I don't think that there is a legitimate reason to have a web server in a JDBC driver.It adds bloat, and tries to do some stuff at startup which takes time.
More pressingly, the shaded javax.servlet classes conflict with minicluster, which breaks the tests in phoenix-queryserver.
Remove Jetty and the Servlet API from the shaded phoenix-client JAR.
We could also consider excluding these dependencies in phoenix-core.