minor #8193 add note about same-state transitions (dbu)

This PR was submitted for the 3.2 branch but it was merged into the 3.3 branch instead (closes #8193).

Discussion
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add note about same-state transitions

maybe this could be made more understandable, but "leave" and "enter" made me think a transition that "stays" in the same place would maybe not trigger those events. i checked the code and tested my application and in fact it works. i think it makes sense to mention this explicitly.

if transitions are explained in more detail somewhere, it could be a good idea to also mention the possibility of same-place transitions there.

Commits
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8736ec2 add note about same-state transitions

Author: javiereguiluz

workflow/usage.rst

@@ -250,7 +250,12 @@ order:
     * ``workflow.[workflow name].announce``
     * ``workflow.[workflow name].announce.[transition name]``
 
-Here is an example of how to enable logging for every time a the "blog_publishing"
+.. note::
+
+    The leaving and entering events are triggered even for transitions that stay
+    in same place.
+
+Here is an example of how to enable logging for every time a "blog_publishing"
 workflow leaves a place::
 
     use Psr\Log\LoggerInterface;