[BUG] Invalid 0 precision token handling /get_tokens

[Avm07]

For 0 precision tokens missing precision field at /get_tokens response data

Example:

curl -X 'GET' \
  'https://hyperion.paycash.online/v2/state/get_tokens?account=i.list' \
  -H 'accept: application/json'

Logical estimate that field will be present:

{
      "symbol": "LQAG",
      "precision": 0,
      "amount": 0,
      "contract": "swap.pcash"
}