test/file: remove fragile test case: test_22566

test/file.jl

@@ -1152,34 +1152,3 @@ end
 test_13559()
 end
 @test_throws ArgumentError mkpath("fakepath", -1)
-
-# issue #22566
-if !Sys.iswindows()
-    function test_22566()
-        fn = tempname()
-        run(`mkfifo $fn`)
-
-        script = """
-            using Test
-            x = open($(repr(fn)), "w")
-            write(x, 0x42)
-            flush(x)
-            Test.@test read(STDIN, Int8) == 21
-            close(x)
-        """
-        cmd = `$(Base.julia_cmd()) --startup-file=no -e $script`
-        p = open(pipeline(cmd, stderr=STDERR), "w")
-
-        r = open(fn, "r")
-        @test read(r, Int8) == 66
-        write(p, 0x15)
-        close(r)
-        @test success(p)
-        rm(fn)
-    end
-
-    # repeat opening/closing fifo file, ensure no EINTR popped out
-    for i ∈ 1:50
-        test_22566()
-    end
-end  # !Sys.iswindows