Update documentation (#1325)
Update documentation (#1325)

* Update documentation

Following this tutorial will current throw an error `Error: Cannot find module '@prisma/client'` at the step for running `node src/script.js` on line 222.  This is solved if we make sure to also install `@prisma/client` alongside `prisma` initially.

* Update 4-adding-a-database.md

Co-authored-by: Tasin Ishmam <dfe88e594936865caa31bc905ac3d38cb6926cc8@gmail.com>
howtographql/howtographql,howtographql/howtographql,howtographql/howtographql