chore: add TimeZones class (#24127)

This adds the time zones in the 2022g release of the Time Zone Database.

It has been tested in the context of the tests written in #23123, but I didn't commit them here because I didn't want to overwrite that change.

I couldn't decide whether this should be a chore or a feat. I'm open to either.

Closes #<issue number here>.

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packages/@aws-cdk/core/lib/index.ts

@@ -68,3 +68,4 @@ export * from './permissions-boundary';
 // class description for more information.
 export * from './private/intrinsic';
 export * from './names';
+export * from './time-zone';