Binding escape as user binding breaks escape sequence bindings (arrows, etc)

Fish 44a5db4d1, which is builtin-path on top of b96c92a7f, also reproduces in 3.3.1:

```fish
bind \e suppress-autosuggestion cancel
```

will essentially break the arrow key bindings. This is because e.g. up-arrow sends `\e\[A`, and this already matches the `\e` and calls it done. Binding it with `--preset` works.

Presumably we're not looking across the lists?