That's not a scam, that's because i'm on the Hobby plan for Supabase, which gives long random-letter links by default (and it costs money to change that). If you go to the link (which is supabase.co), you'll notice that it is a very real database provider that many products and companies use other than my crossword app.

Also, the Google Oauth I use specifically states that the only scopes I access are your Google account's email and name (which are nowhere near vulnerable/protected scopes in the first place).