Drop support for TS 3.4

[trivikr]

trafficstars

Is your feature request related to a problem? Please describe.

Not a problem, but a follow-up to drop support for TS 3.4 version:

• DefinitelyTyped is dropping support for TS 3.4 in March 2021 https://github.com/DefinitelyTyped/DefinitelyTyped#older-versions-of-typescript-33-and-earlier
• The @types/node removed support for TS 3.4 in PR https://github.com/DefinitelyTyped/DefinitelyTyped/pull/51646

Describe the solution you'd like

Drop support for downleveled TS 3.4.x types in AWS SDK for JavaScript (v3)

[github-actions[bot]]

Greetings! We’re closing this issue because it has been open a long time and hasn’t been updated in a while and may not be getting the attention it deserves. We encourage you to check if this is still an issue in the latest release and if you find that this is still a problem, please feel free to comment or open a new issue.

[kuhe]

if we drop support for TS3.4, do should customers downlevel types themselves or simply upgrade their TS version?

[trivikr]

An application can run downlevel-dts on types provides by it's dependencies, but it's usually easier to just upgrade typescript.