Fix comment

Co-authored-by: Peter Donovan <33707478+petervdonovan@users.noreply.github.com>

org.lflang/src/org/lflang/Target.java

@@ -501,7 +501,7 @@ public boolean buildsUsingDocker() {
     }
 
     /**
-     * Whether the target requires using an equal sign to assign a defaul value to a parameter,
+     * Whether the target requires using an equal sign to assign a default value to a parameter,
      * or initialize a state variable. All targets mandate an equal sign when passing
      * arguments to a reactor constructor call, regardless of this method.
      */