removed redundant test (see also 86fac52c2795, a9fea3f11cc0);

--- a/src/Pure/Tools/build.scala	Tue Nov 16 21:21:15 2021 +0100
+++ b/src/Pure/Tools/build.scala	Tue Nov 16 21:43:41 2021 +0100
@@ -493,7 +493,7 @@
         (for {
           session_name <- deps.sessions_structure.imports_topological_order.iterator
           info <- results.get_info(session_name)
-          if selected(session_name) && presentation.enabled(info) && results(session_name).ok }
+          if selected(session_name) && presentation.enabled(info) }
         yield info).toList
 
       if (presentation_sessions.nonEmpty) {