[v1 to v2]: BLANK_LINE node migrating

[JounQin]

Hi! Thanks for your great work first.

I'm currently working on yaml version bump at

prettier/yaml-unist-parser#291

I read the document and tried locally, the BLANK_LINE node type seems been removed on v2, then how can I get and remove the blank lines via v2 API?

[eemeli]

In v2, blank lines show up as boolean spaceBefore properties on nodes.