minor #3511 [Component-DI] Removed useless else statement in code example (saro0h)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #3511).

Discussion
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[Component-DI] Removed useless else statement in code example

Commits
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edca0c7 [Component-DI] Removed useless return
24c4370 [Component-DI] Removed useless else in code example

Author: weaverryan

components/dependency_injection/tags.rst

@@ -199,9 +199,6 @@ To begin with, change the ``TransportChain`` class::
             if (array_key_exists($alias, $this->transports)) {
                return $this->transports[$alias];
             }
-            else {
-               return;
-            }
         }
     }