NIFI-8142 Add "on conflict do nothing" feature to PutDatabaseRecord

[Snorlaxa]

I believe PutDatabaseRecord processor need a feature that we can ignore the record when it already exists in database.

In this implement I add a new Statement Type "INSERT_IGNORE", inspired by @markap14 .

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Enables X functionality; fixes bug NIFI-YYYY.

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[mattyb149]

This PR needs some reorganization, maybe save off the commit(s) where you changed code then reset your branch to match the latest main branch. Then you can put your commits back into the branch (cleaning up any merge conflicts and such). Merging main into your branch usually ends up making things messy.

[mattyb149]

+1 LGTM, ran contrib-check and tried on MySQL, PostgreSQL, and Oracle, all behavior was as expected. However the commit doesn't have the Jira case or description so I will change that before merging, as well as fixing a Checkstyle error. In the future please ensure you run a Maven build (at least for the affected modules) with the -Pcontrib-check profile enabled in order to find any Checkstyle or license issues before posting a Pull Request, that will save time for the reviewers :)

Thanks for the new feature! Merging to main