Search results include "None" entries

[ioalexei]

Searching for Kartoza in the plugin search returns several plugin results but also two entries for "None" which just link back to the search query.

https://plugins.qgis.org/search/?q=kartoza

[Xpirix]

Dear @ioalexei ,

I've fixed it for now. I think that the search index doesn't rebuild automatically when a plugin is deleted. A similar issue has been also reported in the past (#24). I will spend more time to understand how it works and try to prevent it.

Regards.

[Xpirix]

After investigating the issue, I noticed that it is related to the old version of django-haystack currently used (2.8.1).

I did the test locally with the current version 3.2.1 and the search index was rebuilt automatically after deleting/adding a plugin. This version is implemented with the proposed PR #374.