BitArray documentation was lost in the transition from the Gleam Book to the Gleam Language Tour

[nlander]

Most of the content in the BitArray chapter of the Gleam Book has been removed in the corresponding chapter of the Gleam Language Tour. This can be seen by comparing the content of the language tour, as seen here: https://tour.gleam.run/data-types/bit-arrays/ with the content of the book, as seen here: https://web.archive.org/web/20240215102920/https://gleam.run/book/tour/bit-arrays.html