pythongh-137090: Remove redundant statement in Doc/library/concurrent.interpreters.rst (python#137091)

Co-authored-by: Adam Turner <[email protected]>

Author: soolabettu

Doc/library/concurrent.interpreters.rst

@@ -134,7 +134,7 @@ makes them similar to processes, but they still enjoy in-process
 efficiency, like threads.
 
 All that said, interpreters do naturally support certain flavors of
-concurrency, as a powerful side effect of that isolation.
+concurrency.
 There's a powerful side effect of that isolation.  It enables a
 different approach to concurrency than you can take with async or
 threads.  It's a similar concurrency model to CSP or the actor model,