Jolokia is a 100% web concern and does not fit in the Endpoint
infrastructure. This commit removes `JolokiaMvcEndpoint` and exposes
the servlet directly instead while still being part of the
management context. As such, the Jolokia servlet is exposed beneath
the management context path and will move to a separate port when
the management port is not the same as the main server port.

Closes gh-9843