Fix the output path of Artist Background.

The artist background had been saving to the folder the script was run from. This has now been resolved.

api_calls.py

@@ -32,6 +32,12 @@ def get_image(mb_id, ftv_api_key, artist_path):
             if response.status_code == 200:
                 with open(os.path.join(artist_path, 'artist.jpg'), 'wb') as f:
                     f.write(response.content)
+        elif ('artistbackground' in ftv_data):
+            art_url = ftv_data['artistbackground'][0]['url']
+            response = requests.get(art_url)
+            if (response.status_code == 200):
+                with open(os.path.join(artist_path, 'artist.jpg'),'wb') as f:
+                    f.write(response.content)
         elif ('hdmusiclogo' in ftv_data):
             art_url = ftv_data['hdmusiclogo'][0]['url']
             response = requests.get(art_url)