fix: register example (base#424)

Fix base#423. Thanks @manan19!

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## PR-Codex overview
This PR updates the contract interaction in the `create-account.md`
documentation to reflect changes in the address and ABI being used for
nonce retrieval.

### Detailed summary
- Updated the address from `KEY_GATEWAY_ADDRESS` to
`ID_REGISTRY_ADDRESS`.
- Changed the ABI from `keyGatewayABI` to `idRegistryABI`.

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question}`

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Author: horsefacts

docs/developers/guides/accounts/create-account.md

@@ -100,8 +100,8 @@ Collect an EIP-712 `Register` signature from the user. In a real world app, you'
 
 ```ts
 let nonce = await publicClient.readContract({
-  address: KEY_GATEWAY_ADDRESS,
-  abi: keyGatewayABI,
+  address: ID_REGISTRY_ADDRESS,
+  abi: idRegistryABI,
   functionName: 'nonces',
   args: [alice.address],
 });