pub async fn update(host: &Host) -> Result<UpdateOutcome>Expand description
water update: self-update in place when a dist receipt owns the binary;
name the owning package manager’s command for every other channel and
change nothing.
§Errors
Returns an error when the install source cannot be determined (no receipt,
no Homebrew prefix, no CARGO_HOME/bin) or when the updater fails — a
missing receipt, a failed release query, or an installer that exits badly.