docs: update blobstreamx contract addresses (#1482)

Updates contracts to:

Celestia Mainnet -> Arbitrum One: 0xA83ca7775Bc2889825BcDeDfFa5b758cf69e8794
Celestia Mainnet -> Base: 0xA83ca7775Bc2889825BcDeDfFa5b758cf69e8794
Mocha-4 Testnet -> Arbitrum Sepolia: 0xc3e209eb245Fd59c8586777b499d6A665DF3ABD2
Mocha-4 Testnet -> Base Sepolia: 0xc3e209eb245Fd59c8586777b499d6A665DF3ABD2

developers/blobstream.md

@@ -163,9 +163,9 @@ the following Ethereum testnets:
 | Contract     | EVM network      | Contract address                                                                                                                | Attested data on Celestia |
 | ------------ | ---------------- | ------------------------------------------------------------------------------------------------------------------------------- | ------------- |
 | Blobstream X  | Ethereum Mainnet          | [`Not yet deployed`](https://etherscan.io/address/0xTODO) | [Mainnet Beta](../nodes/mainnet.md) |
-| Blobstream X | Arbitrum One | [`Not yet deployed`](https://arbiscan.io/address/0xTODO)  | [Mainnet Beta](../nodes/mainnet.md) |
-| Blobstream X | Base           | [`Not yet deployed`](https://goerli.etherscan.io/address/0xTODO)  | [Mainnet Beta](../nodes/mainnet.md) |
-| Blobstream X | Ethereum Sepolia           | [`0x48B257EC1610d04191cC2c528d0c940AdbE1E439`](https://sepolia.etherscan.io/address/0x48B257EC1610d04191cC2c528d0c940AdbE1E439#events)  | [Mainnet Beta](../nodes/mainnet.md) |
-| Blobstream X | Arbitrum Sepolia           | [`0xf6b3239143d33aefc893fa5411cdc056f8080418`](https://sepolia.arbiscan.io/address/0xf6b3239143d33aefc893fa5411cdc056f8080418#events)  | [Mocha testnet](../nodes/mocha-testnet.md) |
+| Blobstream X | Arbitrum One | [`0xA83ca7775Bc2889825BcDeDfFa5b758cf69e8794`](https://arbiscan.io/address/0xA83ca7775Bc2889825BcDeDfFa5b758cf69e8794#events)  | [Mainnet Beta](../nodes/mainnet.md) |
+| Blobstream X | Base           | [`0xA83ca7775Bc2889825BcDeDfFa5b758cf69e8794`](https://basescan.org/address/0xA83ca7775Bc2889825BcDeDfFa5b758cf69e8794#events)  | [Mainnet Beta](../nodes/mainnet.md) |
+| Blobstream X | Arbitrum Sepolia           | [`0xc3e209eb245Fd59c8586777b499d6A665DF3ABD2`](https://sepolia.arbiscan.io/address/0xc3e209eb245Fd59c8586777b499d6A665DF3ABD2#events)  | [Mocha testnet](../nodes/mocha-testnet.md) |
+| Blobstream X | Base Sepolia           | [`0xc3e209eb245Fd59c8586777b499d6A665DF3ABD2`](https://sepolia.basescan.org/address/0xc3e209eb245Fd59c8586777b499d6A665DF3ABD2#events)  | [Mocha testnet](../nodes/mocha-testnet.md) |
 
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