`gm_send_draft()` not compatible with `gm_drafts()`

[hadley]

library(gmailr)
gm_auth_configure()
gm_auth("h.wickham@gmail.com")

in_drafts <- gm_drafts(num_results = 1)
gm_send_draft(in_drafts[[1]])
#> Error in gm_send_draft(in_drafts[[1]]): has_class(draft, "gmail_draft") is not TRUE

^{Created on 2021-08-05 by the reprex package (v2.0.0)}