PATH is not resolving correctly

使用提供的规则和 payloads 重现 issue #285，然后查看链接的 Mojaloop 讨论，以了解 JSON-PATH 行为的背景。当字符串 body 不满足 $.amount 条件，而包含 amount: '123' 的对象 body 满足该条件，并且已在适当的项目测试中添加回归覆盖时，修复即完成。

I have seen some strange happenings with regard to how the JSON-PATH is resolving in the rules with "json-rules-engine": "6.1.2".

If you consider the following rule:

{
    "ruleId": 1,
    "description": "Returns an NDC exceeded error response (ML error 4001) from the simulator when transfer value is 123 in any currency",
    "conditions": {
        "all": [
            {
                "fact": "path",
                "operator": "equal",
                "value": "/transfers"
            },
            {
                "fact": "method",
                "operator": "equal",
                "value": "POST"
            },
            {
                "fact": "body",
                "operator": "equal",
                "value": "123",
                "path": "$.amount"
            }
        ]
    },
    "event": {
        "type": "simulateError",
        "params": {
            "statusCode": 500,
            "body": {
                "statusCode": "4001",
                "message": "Payer FSP insufficient liquidity"
            }
        }
    }
}

With the following payload:

{
  path: '/transfers',
  body: '123', // <-- Non-matching PATH
  method: 'POST',
}

The rule will still resolve and fire off the event which I believe is incorrect.

My expectation is that it should only resolve when the payload is as follows:

{
  path: '/transfers',
  body: {      // <-- correct body 
      amount: '123',  // <-- Matching PATH
  },
  method: 'POST',
}

Link for reference: https://github.com/mojaloop/mojaloop-simulator/pull/120/files#r747311386