Pre-rendering using 'auto' broken since 1.0.0-next.587

[bradleyg]

Describe the bug

Since 1.0.0-next.587, PR 8131 it seems that using prerender = 'auto' is broken and doesn't pre-render any files.

Reproduction

Stackblitz reproduction

npm run build and then inspect the build folder (there is no prerendered subfolder).
Dropping back down to 1.0.0-next.586 works as expected.

Logs

No response

System Info

  System:
    OS: Linux 5.0 undefined
    CPU: (8) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 0 Bytes / 0 Bytes
    Shell: 1.0 - /bin/jsh
  Binaries:
    Node: 16.14.2 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 7.17.0 - /usr/local/bin/npm
  npmPackages:
    @sveltejs/adapter-node: ^1.0.0 => 1.0.0 
    @sveltejs/kit: 1.0.0-next.587 => 1.0.0-next.587 
    svelte: ^3.54.0 => 3.55.0 
    vite: ^4.0.0 => 4.0.3 

Severity

annoyance

Additional Information

No response