Update downstream Getting Started guide to describe revised deployment mechanism

For the 2022.Q1 release, the Debezium Getting Started guide was published with only minimal updates and it does not include the steps for using the updated build mechanism that AMQ Streams provides.

Update the guide to incorporate the new instructions. The following changes are proposed:

• Change title of guide to specify that it applies to deploying on OCP. Because the title is part of the URL, maybe just add a subtitle, or descriptive text so that links to the guide don't break.

• Remove the steps in Section 2.1, Setting up a Kafka cluster. This section describes the installation of AMQ Streams cluster operator. Replace the steps with links to the Streams Deployment doc for that information.

• In Section 2.2:
  • Remove Step 1 about downloading the MySQL connector. Under the new deployment mechanism, the connector is obtained from the RH Maven repository.
  • Replace content of the section with Steps 1-4 in the UG. Simplify the instructions by omitting references to including scripting or Service Registry bits.

• In Ch 3, Creating a connector to capture inventory database changes:
  • Replace Steps 1 and 2 with Steps 4 and 5 in the UG.
  • Remove Step 3 about verifying the deployment and break that out into a separate subsection as in the UG.