Recover from errors raised when normalizing an URL.

Some URLs can be parsed but when trying to normalize them raise an error, it seems. This should remove some production errors (the problematic URL will be replaced with a blank string).

lib/url_normalizer.rb

@@ -98,7 +98,13 @@ def self.normalize_entry_url(url, entry)
       end
     end
 
-    normalized_url = Addressable::URI.parse(normalized_url).normalize.to_s
+    begin
+      normalized_url = Addressable::URI.parse(normalized_url).normalize.to_s
+    rescue Addressable::URI::InvalidURIError => e
+      Rails.logger.warn "URL #{normalized_url} cannot be normalized, removing it"
+      normalized_url = ''
+    end
+
     return normalized_url
   end