fix(serverless): change response handler type to accept promises

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🦋 Changeset detected

Latest commit: 709715b97fdbc036bb9c182c34f704279e851be6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 12 packages

| Name | Type | | ----------------------------- | ----- | | @ts-rest/serverless | Patch | | @ts-rest/example-contracts | Patch | | @ts-rest/non-strict-mode-test | Patch | | @ts-rest/core | Patch | | @ts-rest/express | Patch | | @ts-rest/fastify | Patch | | @ts-rest/nest | Patch | | @ts-rest/next | Patch | | @ts-rest/open-api | Patch | | @ts-rest/react-query | Patch | | @ts-rest/solid-query | Patch | | @ts-rest/vue-query | Patch |

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Name	Status	Preview	Comments	Updated (UTC)
ts-rest	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	May 3, 2024 0:55am

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Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

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