Rename the "setted_transient" action to "set_transient".

[peterwilsoncc]

To quote the Merriam-Webster dictionary's page for the ​definition for setted:

The word you've entered isn't in the dictionary.

The correct work in the context of the action is "set", so I propose renaming the action to correct the misspelling.

This will also introduce consistency with the action name set_transient_{$transient}.

The incorrectly spelt action is ​used in some popular plugins, the two highest installations with 200K+ active installs, so that may be a blocker due to the amount of log entries it will create. It will not be a back-compat break as it would be covered by a do_action_deprecated() call.