Unskip a few tests (#16946)

* Unskip a few tests

* another one

Author: psfinaki

tests/FSharp.Compiler.ComponentTests/CompilerOptions/fsc/flaterrors.fs

@@ -59,7 +59,7 @@ module flaterrors =
 
     [<InlineData("--FlatErrors")>]                          //Invalid case
     [<InlineData("--FLATERRORS")>]                          //Even more invalid case
-    [<InlineData("--flaterrors-")>]                         // no + allowed
+    [<InlineData("--flaterrors+")>]                         // no + allowed
     [<InlineData("--flaterrors-")>]                         // no - allowed
     [<Theory>]
     let ``E_MultiLine04_fs`` (option: string) =

tests/FSharp.Compiler.ComponentTests/Language/ComputationExpressionTests.fs

@@ -96,7 +96,6 @@ let x = lb {1; 2; if true then 3;}
 
     [<Theory>]
     [<InlineData("preview","BindReturn")>]
-    [<InlineData("preview","BindReturn")>]
     [<InlineData("preview","WithoutBindReturn")>]
     [<InlineData("4.7","BindReturn")>]   
     [<InlineData("4.7","WithoutBindReturn")>]  
@@ -135,4 +134,4 @@ let _pythags = seqbuilder {{
         code
         |> FSharp     
         |> typecheck
-        |> shouldSucceed
+        |> shouldSucceed