Add better error messages to withdraw command

[KartikSoneji]

Inform the user if they are using the wrong keypair or if the candy machine doesn't exist on that network.

Wrong keypair:

wallet public key: 2HFxkoiGDJbCEvduYrJkLD5X7Uwddo2FjmN3jvnWPyy8
Using cluster mainnet-beta
Incorrect wallet for candy machine Ej6MGpsqYLgpfNGcLLQksiNPYWnfvkqqTrEqyHQqWtVb
Candy machine authority is ERRERiw8k8x2pjLAmW12WfMUpw6QKT5MQvCaAD9aUPav
Keypair "id.json" is 2HFxkoiGDJbCEvduYrJkLD5X7Uwddo2FjmN3jvnWPyy8

Candy machine not found:

wallet public key: 2HFxkoiGDJbCEvduYrJkLD5X7Uwddo2FjmN3jvnWPyy8
Using cluster mainnet-beta
Candy Machine Ej6MGpsqYLgpfNGcLLQksiNPYWnfvkqqTrEqyHQqWtVb not found on mainnet-beta

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Name	Status	Preview	Updated
candy-machine-ui	✅ Ready (Inspect)	Visit Preview	May 24, 2022 at 10:13PM (UTC)