Update docs/02-data-exchange.md

Co-authored-by: Alexander Entinger <[email protected]>

Author: sebromero

docs/02-data-exchange.md

@@ -51,7 +51,7 @@ In order to actually facilitate the flow of data from a source to a sink the sin
 DataProducerThread.counter.connectTo(DataConsumerThread_1.counter);
 DataProducerThread.counter.connectTo(DataConsumerThread_2.counter);
 ```
-Whenever a new value is assigned to a data source , i.e.
+Whenever a new value is assigned to a data source, i.e.
 ```C++
 /* DataProducerThread.inot */
 counter = 10;