Added polygon and zksync to the list of chains (#364)

Author: pranavdaa

website/pages/de/developing/supported-networks.mdx

@@ -44,6 +44,8 @@ The following networks are supported in beta on the Hosted Service:
 - `zkSync2-testnet`
 - `osmosis-1`
 - `base-testnet`
+- `polygon-zkevm`(On the studio non rate-limited)
+- `zksync-era`(On the studio non rate-limited)
 
 ### Near