Leak detector is catching goroutines trying to close files which appear
runtime related:
1 instances of:
syscall.Syscall(...)
/usr/local/golang/1.8.3/go/src/syscall/asm_linux_386.s:20 +0x5
syscall.Close(...)
/usr/local/golang/1.8.3/go/src/syscall/zsyscall_linux_386.go:296 +0x3d
os.(*file).close(...)
/usr/local/golang/1.8.3/go/src/os/file_unix.go:140 +0x62
It's unlikely a user goroutine will leak on file close; whitelist it.