Fix typo in docs

Author: tijsrademakers

docs/docusaurus/docs/cmmn/ch06-cmmn.md

@@ -530,7 +530,7 @@ The External Worker task is implemented as a dedicated [Task](cmmn/ch06-cmmn.md#
 <task id="externalWorkerOrder" flowable:type="external-worker">
 ```
 
-The External Worker task is configured by se setting the `topic` (can be an EL expression) which the External Worker uses to query for jobs to execute.
+The External Worker task is configured by setting the `topic` (can be an EL expression) which the External Worker uses to query for jobs to execute.
 
 #### Example usage