Redundant message if only one network

[marsrobertson]

1. Add grant on Optimism and Arbitrum
2. Remove Optimism
3. Checkout

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EDIT / UPDATE: even simpler repro steps:

1. Add grant on Arbitrum
2. Checkout

(previously I was thinking that adding multiple networks sets multiple_networks = true but possible to repro with single network only)

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This message is redundant / confusing:

Checkout all your carts across different networks or select the cart you wish to checkout now.

[linear]

PAR-245 Redundant message if only one network

[Ronexlemon]

can i be assign?

[eben619]

@marsrobertson @MasterHW I'm not sure if this is the fix you are looking for? But does this address the issue?
This is a cart with contributions on more than one network.

So it rightly displays the message on the modal at checkout.

The changes i've made:

Conditional rendering of the message on the modal such that it does not display if the networks being chaecked out in the cart are not more than 1. Even if there are multiple projects in the cart but are on the same network.