Minor typo on auto-fallback.js

[pabloab]

There seems to be a minor typo on auto-fallback.js:

diff  <(npx --shell-auto-fallback bash) <(npx --shell-auto-fallback zsh)
2c2
< command_not_found_handle() {
---
> command_not_found_handler() {

Probably for both it was intended to be command_not_found_handler (with the final r).