[BUG] Registry down for plugins

[annagiovannacci]

Describe the bug
When the plugin page is loaded, an error message is displayed on terminal.
2024-10-01 12:47:01 cheshire_cat_core | [2024-10-01 10:47:01.780] ERROR cat.mad_hatter.registry..registry_search_plugins::50
2024-10-01 12:47:01 cheshire_cat_core | "Error with registry response 500: Internal Server Error"
2024-10-01 12:47:01 cheshire_cat_core | INFO: 172.18.0.1:57556 - "GET /plugins/ HTTP/1.1" 200 OK

Expected behavior
The page should load the available plugins in registry, instead it shows just installed ones.

[pieroit]

Should be up now. Thanks @annagiovannacci