Re-add Iceberg support to Nifi 2

[soenkeliebau]

We did not find any other forks, so we forked the removed Iceberg bundle to https://github.com/stackabletech/nifi-iceberg-bundle
Ideally our fork will be eventually up-streamed again.

For details please read on the repo README.

• Create https://github.com/stackabletech/nifi-iceberg-bundle
• Add to NiFi docker image: feat(nifi): Add nifi-iceberg-bundle docker-images#1060
• Add tests: test: Add test for Apache Iceberg integration #785

[lfrancke]

When implementing this make sure to amend this note #757

[sbernauer]

Docs: https://docs.stackable.tech/home/nightly/nifi/usage_guide/writing-to-iceberg-tables/
Release notes:

Re-add Iceberg support to NiFi 2.4.0, which was removed upstream starting with version 2.0.0