E0324: spread tuple elements cannot be optional

TypeScript tuple types can contain spread elements. By definition, a spread element is optional. It is a syntax error to write ? to mark a spread element as optional:

function foo(...args: [...string[]?, Options]) {
  /* ... */
}

To fix this error, remove the ?:

function foo(...args: [...string[], Options]) {
  /* ... */
}

Introduced in quick-lint-js version 2.10.0.

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