Flink: Upgrade to latest supported Flink versions 2.2 and 2.3

[mxm]

This adds support for Flink 2.2 and 2.3 and removes support for Flink 2.0 and 2.1, as per mailing list discussions:

1. https://lists.apache.org/thread/kd183vz2v2y69v4kwbz5wbjfxvx3gf1f
2. https://lists.apache.org/thread/8fsqcovm1cn7zdl571t4f9qlyqgf5qxy

Consequently, the supported Flink versions are now 1.20, 2.2, 2.3 (was: 1.20, 2.0, 2.1).

The actual set of changes are very small, see 05dd0c2.

[RussellSpitzer]

License merge conflicts, @mxm also please be sure to double check any effected licensing changes we need to make in the root License or Notice file of the fat jar

[talatuyarer]

@mxm I created another PR to keep 2.1 and drop 2.0 #17849