Update validation cloud mainnet rpc status (#756)

Co-authored-by: Jane Wang <[email protected]>

docs/reference/rpc-list.mdx

@@ -12,7 +12,7 @@ These providers allow access to the Testnet and Mainnet networks.
 | Provider                                                | Access                                              | Futurenet     | Testnet   | Mainnet     |
 | ------------------------------------------------------- | --------------------------------------------------- | ------------- | --------- | ----------- |
 | [Blockdaemon](https://www.blockdaemon.com)              | [Access](https://www.blockdaemon.com/apply/soroban) | Not available | Available | Available   |
-| [Validation Cloud](https://validationcloud.io/)         | [Access](https://app.validationcloud.io/)           | Not available | Available | Coming soon |
+| [Validation Cloud](https://validationcloud.io/)         | [Access](https://app.validationcloud.io/)           | Not available | Available | Available   |
 | [QuickNode\*](https://www.quicknode.com/chains/stellar) | [Access](https://www.quicknode.com/chains/stellar)  | Not available | Available | Available   |
 | [NowNodes](https://nownodes.io/nodes/stellar-xlm)       | [Access](https://nownodes.io/nodes/stellar-xlm)     | Available     | Available | Coming soon |
 | [Gateway](https://gateway.fm/)                          | [Access](https://gateway.fm/public-rpc/)            | Not available | Available | Available   |