MySQL connector registers JMX metrics streaming bean with context binlog [DBZ-1502]

Migrated from [DBZ-1502](https://issues.redhat.com/browse/DBZ-1502)

Connectors that expose JMX metrics register the JMX beans with the following unified contexts:
# schema-history
# snapshot
# streaming

The exception to this is that MySQL registers the streaming from the binlog with {{context=binlog}} rather than {{context=streaming}}.
This should be unified across all connectors.

Start by locating the MySQL connector's JMX metrics registration and compare its streaming context with the schema-history and snapshot contexts used by other connectors. Verify the relevant tests or add coverage for the registration behavior. Done means MySQL exposes binlog streaming metrics with context=streaming rather than context=binlog.

Written by the indexing model from the issue text.