Add rpcfree.com public RPC for Base (#8355)

Co-authored-by: Bogdan Mavrodin <b.mavrodin@gmail.com>

Author: etoxdev

_data/chains/eip155-8453.json

@@ -7,7 +7,8 @@
     "https://base.gateway.tenderly.co",
     "wss://base.gateway.tenderly.co",
     "https://base-rpc.publicnode.com",
-    "wss://base-rpc.publicnode.com"
+    "wss://base-rpc.publicnode.com",
+    "https://rpcfree.com/base-rpc"
   ],
   "faucets": [],
   "nativeCurrency": {