Providing a comma-separated list of specs in an API call is not working

[agoldis]

Before opening, please confirm:

• [X] I have searched for duplicate or closed issues and discussions.
• [X] I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.
• [X] I acknowledge that I will attach a full debug log, otherwise the issue will be closed with no response.

Environment information

n/a

Describe the bug

This does not work:

await run({
    // this does not work
    spec: "cypress/integration/1000.spec.js,cypress/integration/fails.spec.js",
    ciBuildId: "xome",
  })

This works:

 await run({
    // this works
    spec: [
      "cypress/integration/1000.spec.js",
      "cypress/integration/fails.spec.js",
    ],
    ciBuildId: "xome",
  })

Expected behavior

spec: "cypress/integration/1000.spec.js,cypress/integration/fails.spec.js",

should work

Command and Setup

n/a

Full log and debug output

n/a