Switch to using ParityDB by default

[lemmih]

Issue summary

ParityDB performs better and uses less memory than RocksDB. Let's use it by default.

• Update build files in Forest.
• Make sure our docker files don't install unnecessary dependencies.
• Update the CHANGELOG.

Other information and links

[lemmih]

Blocked by #2278

[LesnyRumcajs]

Blocked by #2278

Doesn't seem to be directly related to ParityDb; I'd remove it as a blocker.

[elmattic]

Maybe we could remove (rocks_db member) in Config struct as well.

[LesnyRumcajs]

We don't want to remove RocksDb, only deprecate it in a way. As far as I remember, it needs to be there for serialisation reasons. Or am I missing something?

[elmattic]

Yeah, it's here if you have an old config file, with some RocksDb config section.