minor #8252 Fixed typo in workflow.announce event description (yann-eugone)

This PR was merged into the 3.3 branch.

Discussion
----------

Fixed typo in workflow.announce event description

Maybe I'm wrong but I think that the term `place` is confusing here.
I assume that **transitions** are announced.

Commits
-------

41b8671 Fixed typo in workflow.announce event description

Author: xabbuh

workflow/usage.rst

@@ -241,7 +241,7 @@ order:
     * ``workflow.[workflow name].entered.[place name]``
 
 ``workflow.announce``
-    Triggered for each place that now is available for the object.
+    Triggered for each transition that now is accessible for the object.
 
     The three events being dispatched are: