chore: remove p-every

[43081j]

We can achieve this with Promise.all and no longer need a dependency.

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[43081j]

@mrstork or @serhalp this edge function failure we get across a bunch of PRs right now:

   ❯ node/server/server.test.ts (2 tests | 2 failed) 2968ms
     × Starts a server and serves requests for edge functions 998ms
       → expected 500 to be 200 // Object.is equality
     × Serves edge functions in a monorepo setup 1969ms
       → expected 500 to be 200 // Object.is equality

the hosted serve function looks like this:

export const serve = (
  functions: () => Promise<Record<string, EdgeFunction>>,
) => {
  // ...
}

but the functions we pass in from our tests look like this:

  const declaration = `const functions = {}; const metadata = { functions: {} };`

im guessing the hosted server changed and it gets cached heavily, which is why some builds and people still get passing test runs but others don't

i've shown the change in #6587

[mrstork]

Thank you!