removing double engine declaration for Google Image

Author: hilmanski

README.md

@@ -333,7 +333,6 @@ import serpapi
 
 client = serpapi.Client(api_key=os.getenv("API_KEY"))
 results = client.search({
-    'engine': 'google_images',
     'engine': 'google_images',
     'tbm': 'isch',
     'q': 'coffee',