docs: fix spelling untill -> until
docs: fix spelling untill -> until

Co-Authored-By: Jonas Platte <27ee6ecc1a7094fc3a72464b18d8f78fff8631eb@users.noreply.github.com>
rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer