As of #23867 this is now a real package, so updating the imports to
use the real package name, rather than relying on the alias. The
name change in the package name is because `I18n` is not a valid
name as NPM packages must be all lowercase.
This commit also introduces an eslint rule to prevent importing from
the old I18n path.
For themes/plugins, the old 'i18n' name remains functional.
Essentially,
Saturday at 2:50 PM -> Saturday at 4:38 PM becomes
Saturday at 2:50 PM -> 4:38 PM (Singapore)
Also, the displayed dates are shortened when the standalone date
is within two days. So despite the 'from' and 'to' date being the
same day, it may show 'Saturday' for 'from', and the specific date
for the 'to'. This corrects the behaviour.
(so if the current date and time is Thursday 5PM, the 'from' date
below is within 2 days, but the 'to' date is not)
Saturday at 2:50 PM -> 8 October 2022 at 9:38 PM becomes
Saturday at 2:50 PM -> 9:38 PM
