feat(booking) [PPT-1942] include parent in json

[chillfox]

No description provided.

[github-actions]

Hey, your PR is titled feat(booking) [PPT-1942] include parent in json.
This is not a valid conventional commit.
Since we use well-formed PR titles for our changelogs, not fixing this can introduce problems :'(

[stakach]

are we doing this on an index route? or just in a show route
if on the index route then we should also implement a helper function that:

1. accepts an array of bookings
2. finds all the ones that have a parent id
3. makes a single query to fetch all the parent ids
4. applies the parent object to the bookings

This way we make 2 database requests instead of N+1

[stakach]

Made a couple of minor tweaks. Looks good