C#: Update test expected output.

Author: michaelnebel

csharp/ql/test/query-tests/Useless Code/FutileConditional/FutileConditional.expected

@@ -1,7 +1,3 @@
-#select
 | FutileConditional.cs:8:9:8:27 | if (...) ... | If-statement with an empty then-branch and no else-branch. |
 | FutileConditional.cs:10:9:12:9 | if (...) ... | If-statement with an empty then-branch and no else-branch. |
 | FutileConditional.cs:22:9:27:9 | if (...) ... | If-statement with an empty then-branch and no else-branch. |
-| FutileConditional.cs:29:9:32:9 | if (...) ... | If-statement with an empty then-branch and no else-branch. |
-testFailures
-| FutileConditional.cs:29:9:32:9 | If-statement with an empty then-branch and no else-branch. | Unexpected result: Alert |