Plugin isn't working properly

Hi! First of all, many thanks for this useful project!

I am now trying to execute [this plugin](https://github.com/lightningd/plugins/tree/master/rebalance) on one of the spawned nodes with various channels and getting the following error:
```
{
"code": -32600,
"message": "Error while processing rebalanceall: int() argument must be a string, a bytes-like object or a number, not 'dict'",
"traceback": "Traceback (most recent call last):\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/plugin.py\", line 639, in _dispatch_request\n result = self._exec_func(method.func, request)\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/plugin.py\", line 616, in _exec_func\n ret = func(*ba.args, **ba.kwargs)\n File \"/root/run/plugins/rebalance/rebalance.py\", line 677, in rebalanceall\n channels = get_open_channels(plugin)\n File \"/root/run/plugins/rebalance/rebalance.py\", line 415, in get_open_channels\n for peer in plugin.rpc.listpeers()[\"peers\"]:\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/lightning.py\", line 999, in listpeers\n return self.call(\"listpeers\", payload)\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/lightning.py\", line 384, in call\n resp, buf = self._readobj(sock, buf)\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/lightning.py\", line 312, in _readobj\n obj, _ = self.decoder.raw_decode(parts[0].decode(\"UTF-8\"))\n File \"/usr/lib/python3.9/json/decoder.py\", line 353, in raw_decode\n obj, end = self.scan_once(s, idx)\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/lightning.py\", line 494, in millisatoshi_hook\n obj = LightningRpc.LightningJSONDecoder.replace_amounts(obj)\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/lightning.py\", line 485, in replace_amounts\n obj[k] = Millisatoshi(v)\n File \"/usr/local/lib/python3.9/dist-packages/pyln/client/lightning.py\", line 70, in __init__\n elif int(v) == v:\nTypeError: int() argument must be a string, a bytes-like object or a number, not 'dict'\n"
}
```
I have previously used this plugin on both `testnet` and `mainnet` networks, and it worked fine. The plugin itself is installed correctly, I guess there's some kind of error in the environment?

The entry point is in this plugin call.

```
def get_open_channels(plugin: Plugin):
channels = []
for peer in plugin.rpc.listpeers()["peers"]:
for ch in peer["channels"]:
if ch["state"] == "CHANNELD_NORMAL" and not ch["private"]:
channels.append(ch)
return
```
And leads to this method in `lightning.py`

```
def listpeers(self, peerid=None, level=None):
"""
Show current peers, if {level} is set, include {log}s".
"""
payload = {
"id": peerid,
"level": level,
}
return self.call("listpeers", payload)
```

Thank you very much in advance for your help!