New filters in jq 1.7

[kklingenberg]

These are:

• [ ] pick/1 which I believe must be implemented natively, since it involves preserving path information.
• [ ] abs/0 which is apparently trivial, though from the release notes I guess it'd also need to be native since it should preserve Val::Num variants. Maybe it's as simple as preserving the variant here?

Source: https://github.com/jqlang/jq/releases/tag/jq-1.7