async function createOniguruma(options) {
  const wasmBinary = await getOniguruma(options || undefined)
  await vscodeOniguruma.loadWASM(wasmBinary)
  return vscodeOniguruma
}
Small function needed for oniguruma to work.

Idea: as this seems to be a singleton, would it help if we call it once and
keep the promise?

@param {Readonly<Options> | null | undefined} [options]
  Configuration (optional).
@returns
  `vscode-oniguruma`.