Remove pipestatus expect test

This doesn't really do more than the check of the same name.

tests/pipestatus.expect

@@ -1,79 +0,0 @@
-# vim: set filetype=expect:
-#
-# Verify `$pipestatus` is preserved to next prompt.
-
-spawn $fish
-
-expect_prompt
-
-# no pipe
-send_line "true"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "0 : 0" {}
-send_line "false"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "1 : 1" {}
-
-# no pipe but negated
-send_line "! true"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "0 : 1" {}
-send_line "! false"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "1 : 0" {}
-
-# pipe
-send_line "false | true | false"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "1 0 1 : 1" {}
-
-# pipe negated
-send_line "! false | true | false"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "1 0 1 : 0" {}
-
-# pipe mixed with builtins and external
-send_line "command true | false | true | true"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "0 1 0 0 : 0" {}
-send_line "command true | command false | command false"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "0 1 1 : 1" {}
-send_line "sh -c 'exit 3' | command false | sh -c 'exit 5'"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "3 1 5 : 5" {}
-
-# negated pipe with mixed builtin and external
-send_line "! sh -c 'exit 3' | command false | sh -c 'exit 5'"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "3 1 5 : 0" {}
-
-# block
-send_line "command false | begin; command true; end | true"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "1 0 0 : 0" {}
-send_line "command false | begin; ! true; end | true"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "1 1 0 : 0" {}
-
-# syntax error
-send_line "syntax terror"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "127 : 127" {}
-send_line "syntax | terror"
-expect_prompt
-send_line "echo \$pipestatus : \$status"
-expect_prompt "127 : 127" {}