Update sd-civitai-browser-plus name and description

[BlafKing]

Info

I've made a small edit to my extension.json which is already added to the database.

I've changed the name (to match the naming I use on my repo) and I've changed the description since I've added quite a lot of features since the first merge request of the extension.

(Haven't changed the index.json with the new naming/description, since it was requested to not do so)

Checklist:

• I have read the Readme.md
• The description is written in English.
• The index.json and extension_template.json have not been modified.
• The entry is placed in the extensions directory with the .json file extension.