Update class-wc-checkout.php

Removing the word "to" from the error message indicating that a site doesn't ship to a certain country.

The function, shipping_to_prefix(), will handle insert the word "to".
Or, in the case of US, GB, and a few other countries, the words "to the".
#5613 Typo in "don't ship to" error message

Typo in "don't ship to" country message: Issue #5613

Removing the word "to" from the error message indicating that a site doesn't ship to a certain country.

The function, shipping_to_prefix(), will handle insert the word "to".
Or, in the case of US, GB, and a few other countries, the words "to the".
Merge pull request #5614 from mkayan-wakefly/master

RE issue: #5613 - Typo in error message