fix(docs): clarify trigger with concurrency

Author: wrussell1999

content/docs/04.workflow-components/14.concurrency.md

@@ -70,6 +70,9 @@ As you can see in the UI, the third execution failed as the first two executions
 
 ![concurrency_fail](/docs/workflow-components/concurrency_fail.png)
 
+::alert{type="warning"}
+When an execution is started by a [Schedule Trigger](./07.triggers/01.schedule-trigger.md), that trigger will lock until the execution is done, preventing multiple executions from that trigger to run concurrently. This means the `behavior` property will not come into effect and instead no new executions will be started.
+::
 
 ## Tracking Concurrency Slots from the UI