fix(extract_movie_popular_reviews): Fix extract_rating, add extract_review_likes

[Investigamer]

What this PR does:

• Replaces the current extraction pattern for collecting the star rating of a review. This rating is returned as a float value 0-5 if the element is found, otherwise None. It does this by counting the stars and half stars exposed by the aria-label of the SVG.
• Adds a new field to review data: "likes". The amount of likes a review has is neatly exposed in a "data-count" attribute of a <p> element in every review. This value is returned as an integer if present, otherwise as None.
• Adds return type to a few existing nested functions

I've tested this methodology against several movie pages, haven't encountered a failure thus far :) Would very much like to see this minor improvement checked into the project, if at all possible. Thanks!