Complete the documentation of the workflow options

[javiereguiluz]

In #11041 we listed the workflow config options to complete the config reference. Now someone who knows the Workflow component well must add the docs for those options.

Keep in mind that in /workflow/*.rst we have several articles explaining workflows and state machines, so we don't have to repeat everything in the config reference.

Thanks!

[noniagriconomie]

@javiereguiluz I give it a try on #11492

[javiereguiluz]

Fixed by #11492.