I’d suggest:
document.querySelector('.rateRecipe.btns-one-small').click();
The above code assumes that the given element has both of those classes; otherwise, if the space is meant to imply an ancestor-descendant relationship:
document.querySelector('.rateRecipe .btns-one-small').click();
The method getElementsByClassName() takes a single class-name (rather than document.querySelector()/document.querySelectorAll(), which take a CSS selector), and you passed two (presumably class-names) to the method.
References:
document.getElementsByClassName().document.querySelector().