move irrelevant code out of client-java repo

[zz-jason]

Feature Request

Is your feature request related to a problem? Please describe:

client-java is a SDK for interaction between java apps and tikv cluster, just like client-go, client-rust

there are some packages that are irrelevant to the target goals, like:

1. org.tikv.cdc: a library to manipulate CDC events
2. org.tikv.br: a library to manipulate BR SST files
3. coprocessor

Describe the feature you'd like:

move these irrelevant libraries to a better place, for example, CDC an be can be moved to https://github.com/tikv/migration

Describe alternatives you've considered:

N/A

Teachability, Documentation, Adoption, Migration Strategy:

N/A

[zz-jason]

@birdstorm @marsishandsome PTAL

[birdstorm]

Agree. The support for CDC and BR could be moved to an individual library.

[marsishandsome]

LGTM

[github-actions]

This issue is stale because it has been open 30 days with no activity.