Explain the Concept of “Rug Pull” in Relation to Mutable Contract Ownership

A "rug pull" is a malicious act where the developers of a project suddenly withdraw all liquidity or funds from a contract, often after hyping the project. In a mutable contract, a rug pull can be executed by using the admin key to perform a malicious upgrade that changes the contract logic to include a function that allows the owner to drain the funds held by the contract.