Fix DATABASE_URL environment variable for prisma validate in gated-deployment workflow

Co-authored-by: johndoe6345789 <224850594+johndoe6345789@users.noreply.github.com>

.github/workflows/gated-deployment.yml

@@ -78,6 +78,8 @@ jobs:
 
       - name: Validate database schema
         run: bunx prisma validate
+        env:
+          DATABASE_URL: file:./dev.db
 
       - name: Check for breaking changes
         id: breaking