fix: update codespaces on create script (#1034)

## Description

Updates the `on-create.sh` script to use our `dx` command resolving
issues where it couldn't find the docker compose file due to changes
that have happened since publishing the Documenso docker image.

## Related Issue

Resolves #1026

## Test Details

N/A

## Checklist

- [x] I have written the new test and ensured it works as intended.
- [x] I have added necessary documentation to explain the purpose of the
test.
- [x] I have followed the project's testing guidelines and coding style.
- [x] I have addressed any review feedback from previous submissions, if
applicable.

## Additional Notes

N/A

.devcontainer/on-create.sh

@@ -1,13 +1,10 @@
 #!/usr/bin/env bash
 
-# Start the database and mailserver
-docker compose -f ./docker/compose-without-app.yml up -d
-
 # Install dependencies
 npm install
 
 # Copy the env file
 cp .env.example .env
 
-# Run the migrations
-npm run prisma:migrate-dev
+# Run the dev setup
+npm run dx