Create new abandoned package preset and add to config:best-practices

[rarkins]

Describe the proposed change(s).

config:best-practices should have a new default of 1 year for abandonmentThreshold, but in addition we should add a new file in https://github.com/renovatebot/renovate/tree/main/lib/data which allows for community-sourced overrides which get converted into packageRules. This overrides file can contain a single entry to begin with / use as an example: npm's lodash. Although it's had no release in ~4 years, it's not fully abandoned - for example the maintainers recently added a SECURITY.md file to the repo.