FIX: Do not fail-stop if theme update fails (#15063)

lib/tasks/themes.rake

@@ -61,14 +61,11 @@ def update_themes
         theme.save!
         unless theme.remote_theme.last_error_text.nil?
           puts "Error updating '#{theme.name}': #{theme.remote_theme.last_error_text}"
-          exit 1
         end
       end
     rescue => e
-      STDERR.puts "Failed to update '#{theme.name}'"
-      STDERR.puts e
+      STDERR.puts "Failed to update '#{theme.name}': #{e}"
       STDERR.puts e.backtrace
-      exit 1
     end
   end
 end