Use API key to access the DB instead of public shared link.

[elrumo]

Currently, the Figma plugin is asking the user to insert a public shared link to the database, and a third party service API is used to get the table's key to access the data. However, this method only gives the plugin access to one table view, so if data from other tables from the database is to be accessed, the user would have to share another link. A solution to this, albeit a bit cumbersome, is to ask the user to manually find their personal API key and the key to the database.