test(spec-sdk): fix paginator response shape after Speakeasy 1.753.0

[alexluong]

Speakeasy CLI bump (1.741.7 → 1.753.0, commit 3f311e0d) wrapped list-operation responses in a PageIterator. The change wasn't flagged in the SDK regen PR changelog, so spec-sdk-tests silently went stale.

Before:

const response = await sdk.events.list({ tenantId });
const events = response.models;

Now:

// Direct access to the first page
const response = await sdk.events.list({ tenantId });
const events = response.result.models;

// Or iterate across pages
const response = await sdk.events.list({ tenantId });
for await (const page of response) {
  for (const event of page.result.models) { ... }
}

// Or step manually via the paginator
let page = await sdk.events.list({ tenantId });
while (page) {
  for (const event of page.result.models) { ... }
  page = await page.next();
}

This PR updates the affected tests (events.test.ts, tenants.test.ts) to the new accessor.

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Not necessarily my personal preference (the extra result wrapper feels noisy for the common single-page case), but it appears to be Speakeasy convention for paginated operations — keeps the iterator metadata (next, [Symbol.asyncIterator]) co-located with the parsed body without colliding with response fields.

[alexbouchardd]

Can't we change that? That seems like a totally uncecessary breaking change that actually worst then before...

[alexluong]

Agreed that I don't prefer this either, will look into if there's a way to revert this behavior.