Updating documentation on supabase DATABASE_URL

[mireklzicar]

Describe the feature or enhancement

I am using umami with supabase and with the latest version, only POSTGRES_URL_NON_POOLING (Supavisor URL on session mode) works with umami when set as DATABASE_URL. others like POSTGRES_PRISMA_URL or POSTGRES_URL do not work.

This was already noted in these issues:

• Schema engine error - prepared statement "s0" already exists #2989

Proposal:

• updating the documentation at https://umami.is/docs/guides/running-on-supabase
• extends as well to vercel+supabase integration

[nayasinghania]

I also found this to be an issue when using umami with Supabase with PostgreSQL. My workaround was to get the appropriate values for my .env from the "Prisma" tab of Supabase's connect page and update the Prisma schema file accordingly (see https://github.com/accuguide/umami/blob/master/db/postgresql/schema.prisma). Hoping an official fix to this will be made in future versions of umami.