Light client hangs when calling light server via json-rpc

[adamschmideg]

Here is what I do. I run three terminals

1. geth --goerli --datadir foo --lightserv 100 --rpc -rpcapi personal,eth,net,web3b,les
2. geth --syncmode "light" --rpc --datadir bar --port 30304 --rpcport 8546 --goerli console
3. geth --datadir foo attach

In the 2nd terminal I run admin.nodeInfo.id to get the nodeID
In the 3rd terminal I execute

les.addBalance(<nodeID>, 100000, "whatever")
les.clientInfo([<nodeID>])

The client in the 3rd terminal hangs. I can't see any error message in the first terminal.

[rjl493456442]

Fixed by #20395