Company - POST/PUT - Admins creating a second company are removed from the first.

[Anclagen]

When a client that is an admin for an existing company creates a second company they are removed from the initial company without its deletion.

Possible solutions:

1. A check preventing an admin from creating a new company or being added to another company without first leaving/deleting their current company.
2. Allow clients to be admins in multiple companies and update the prisma schema to allow this.