Hi Ben,
Thank you for posting your concern.
Upon testing the line that you provided, I was able to replicate the error. The reason why you are seeing the error is because of the double-byte characters (left single quotation mark ‘ and right single quotation mark ’) which are enclosing the sheet name. You may use single quotations (apostrophe) ' instead of the double-byte characters.
var SHEET_NAME = 'brs';
Please let me know how it goes after trying the suggestion above.
Regards,
Hiroyuki
Google Ads Scripts Team