This pathc fixes the render of the first page. This one have to display
general results plus a sample of 5 images and 2 videos.

Previously, torrent and videos results were included.

This change is related to the comment https://gitlab.e.foundation/e/cloud/my-spot/issues/30#note_10233

This reverts commit 63e8c8b1.

Fix google image search engine

- Because there is not full image url in the dom, we replace "image_url" with the same url as the "url" (url of source).
  See example HTML https://gist.github.com/Nachtalb/2dea8a4d2c723c49226ad9645838121f
- Remove unused import
- Fix google image search title
- Keep google image safe value up to date

[fix] DuckDuckGo Images requests

In order to use another cache tool or to use spot without cache
system.

The new redis version is more strict about the kind of object
to store, we cannot use the same way that with the version 2.X.
In redis we want to store the SearchData class. Instead of
store field one by one we store the full serialized object with pickle.

Pickle is not very secure but we dont care for now because the redis
storage will be deploy in the same host that spot service. In a second time
we can use another way to serialize SearchData with msgpack and mashumaro
for example.

Use HTTPS for crossref

[fix] get YouTube results

[fix] Stop engine from sending duplicated requests

SearchData is composed by SearchQuery field, so we use inheritance
in order to use the same field naming. In that way we can use the an
uniq way to build our redis key.