fixed allocation creation

[prekucki]

Test:

$ yagna payment accounts --json
[]

$ python -m venv venv
$ . venv/bin/activate
$ pip install git+https://github.com/golemfactory/yapapi.git@prek/b0.10-fixes

$ python ssh.py
...

$ yagna payment accounts --json
[
  {
    "address": "0x889ff52ece3d5368051f4f8216650a7843f8926b",
    "driver": "erc20",
    "network": "goerli",
    "platform": "erc20-goerli-tglm",
    "receive": false,
    "send": true,
    "token": "tGLM"
  }
]