Parameters for action=edit as a plain object, or null to cancel the edit.
May also return a Promise resolving to either of the two.
See Mwbot.edit for the default parameters used by the method.
If the return value is (or resolves to) null, the method rejects with a MwbotError
using the api_mwbot: aborted error code.
Callback function for Mwbot.edit.