Add note about Heroku SSL connection (#7039)

Co-authored-by: Patrick Jakubik <37963339+patryk-smc@users.noreply.github.com>
Co-authored-by: Aidan McAlister <105178005+aidankmcalister@users.noreply.github.com>

Author: patjakubik

content/200-orm/200-prisma-client/500-deployment/101-traditional/200-deploy-to-heroku.mdx

@@ -269,6 +269,18 @@ const server = app.listen(PORT, () => {
 
 - **Database URL**: As part of Heroku's provisioning process, a `DATABASE_URL` config var is added to your app’s configuration. This contains the URL your app uses to access the database. Ensure that your `schema.prisma` file uses `env("DATABASE_URL")` so that Prisma Client can successfully connect to the database.
 
+* **Disable SSL certificate validation**: When using the `PrismaPg` adapter with `DATABASE_URL`, make sure to disable SSL certificate validation in line with [Heroku's guidelines](https://devcenter.heroku.com/articles/connecting-heroku-postgres#connecting-in-node-js). Failing to do so can result in a `P1010 DriverAdapterError: DatabaseAccessDenied` error. You can handle this conditionally based on whether the database is local or hosted on Heroku:
+
+```js
+const isSecureDb = !process.env.DATABASE_URL.includes("@127.0.0.1")
+
+export const db = new PrismaClient({
+  adapter: new PrismaPg({
+    connectionString: process.env.DATABASE_URL + (isSecureDb ? `?sslmode=no-verify` : "")
+  })
+})
+```
+
 ## Summary
 
 Congratulations! You have successfully deployed a Node.js app with Prisma ORM to Heroku.