confirm element: pressing a function key throws an error

[ohana54]

Describe the bug

Using the confirm element, pressing one of the function keys (F1/F2...) throws an error.

To Reproduce

Steps to reproduce the behavior:

1. Use the confirm element:

prompts({
  type: 'confirm',
  message: 'x',
});

2. Press F2

Expected behavior

No error should be thrown

System

• OS: MacOS 12.5.1
• Terminal: iTerm
• Node version: 18.16.0

Additional context

Full stack trace:

node:internal/readline/emitKeypressEvents:71
            throw err;
            ^

TypeError: Cannot read properties of undefined (reading 'toLowerCase')
    at ConfirmPrompt._ (/node_modules/prompts/lib/elements/confirm.js:60:11)
    at ReadStream.keypress (/node_modules/prompts/lib/elements/prompt.js:30:24)
    at ReadStream.emit (node:events:513:28)
    at emitKeys (node:internal/readline/utils:357:14)
    at emitKeys.next (<anonymous>)
    at ReadStream.onData (node:internal/readline/emitKeypressEvents:61:36)
    at ReadStream.emit (node:events:525:35)
    at addChunk (node:internal/streams/readable:315:12)
    at readableAddChunk (node:internal/streams/readable:289:9)
    at ReadStream.Readable.push (node:internal/streams/readable:228:10)