Fix docs build when no debug build present, suppress signature file var name mismatch errors

Author: beauvankirk

build.fsx

@@ -127,7 +127,7 @@ Target.create "NuGet" (fun _ ->
 
 Target.create "GenerateDocs" (fun _ ->
     Shell.cleanDir ".fsdocs"
-    DotNet.exec id "fsdocs" "build --clean" |> ignore
+    DotNet.exec id "fsdocs" "build --clean --properties Configuration=Release" |> ignore
 )
 
 // --------------------------------------------------------------------------------------

src/FSharp.Control.AsyncSeq/AsyncSeq.fs

@@ -12,7 +12,7 @@ open System.Threading.Tasks
 open System.Runtime.ExceptionServices
 open System.Linq
 
-#nowarn "40"
+#nowarn "40" "3218"
 
 // ----------------------------------------------------------------------------