Add Nownodes (#2253)

README.md

@@ -192,6 +192,7 @@ API | Description | Auth | HTTPS | CORS |
 | [Bitquery](https://graphql.bitquery.io/ide) | Onchain GraphQL APIs & DEX APIs | `apiKey` | Yes | Yes |
 | [Chainlink](https://chain.link/developer-resources) | Build hybrid smart contracts with Chainlink | No | Yes | Unknown |
 | [Covalent](https://www.covalenthq.com/docs/api/) | Multi-blockchain data aggregator platform | `apiKey` | Yes | Unknown |
+| [Nownodes](https://nownodes.io/) | Blockchain-as-a-service solution that provides high-quality connection via API | `apiKey` | Yes | Unknown |
 
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