Revert "Let's also thumbnail the now playing widget"

This reverts commit 76cc1f7b1c.

vrobbler/apps/scrobbles/mixins.py

@@ -44,7 +44,7 @@ class ScrobblableMixin(TimeStampedModel):
         abstract = True
 
     @property
-    def primary_image(self) -> Optional["ImageField"]:
+    def primary_image_url(self) -> str:
         logger.warn(f"Not implemented yet")
         return ""