fix: custom endpoints with method: 'put'

[r1tsuu]

What?

Fixes support for custom endpoints with method: 'put'.
Previously, this didn't work:

export default buildConfigWithDefaults({
  collections: [ ],
  endpoints: [
    {
      method: 'put',
      handler: () => new Response(),
      path: '/put',
    },
  ],
})

Why?

We supported this in 2.0 and docs are saying that we can use 'put' as method https://payloadcms.com/docs/beta/rest-api/overview#custom-endpoints

How?

Implements the REST_PUT export for @payloadcms/next/routes, updates all templates. Additionally, adds tests to ensure root/collection level custom endpoints with all necessary methods execute properly.

Fixes #8807

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[github-actions]

🚀 This is included in version v3.0.0-beta.125