Remove link to non-existing page

docs/pfdl/task.md

@@ -4,7 +4,7 @@ SPDX-License-Identifier: MIT
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 # Task
 A Task is an executable unit which executes the statements within sequentially.
-The name of the Task should be a [lowercase string](../#allowed-characters).
+The name of the Task should be a string that starts with a lowercase character.
 
 ## The Production Task
 A Task with the name `productionTask` serves as the starting point of the production order.