Added Hapi integration to the list (#7138)

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Author: arimus

docs/source/integrations/integration-index.mdx

@@ -17,6 +17,7 @@ The larger community maintains the following open-source integrations for Apollo
 |--------|-------------|
 | [AWS Lambda](https://aws.amazon.com/lambda/) | [`@as-integrations/aws-lambda`](https://www.npmjs.com/package/@as-integrations/aws-lambda) |
 | [Fastify](https://fastify.io/) | [`@as-integrations/fastify`](https://www.npmjs.com/package/@as-integrations/fastify) |
+| [Hapi](https://hapi.dev/) | [`@as-integrations/hapi`](https://www.npmjs.com/package/@as-integrations/hapi) |
 | [Koa](https://koajs.com/) | [`@as-integrations/koa`](https://www.npmjs.com/package/@as-integrations/koa) |
 | [Next.js](https://nextjs.org) | [`@as-integrations/next`](https://www.npmjs.com/package/@as-integrations/next) |
 | [Nuxt](https://v3.nuxtjs.org/) / [h3](https://github.com/unjs/h3) | [`@as-integrations/h3`](https://www.npmjs.com/package/@as-integrations/h3) |