Exception when triggering Lambda based API from Cloudwatch Events

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*Serverless Java Container version*: `1.5.1`

*Implementations:* `Spring Boot 2`

*Framework version:* `SpringBoot 2.2.6.RELEASE`

*Frontend service:* `AWS Cloudwatch Events`

*Deployment method:* `Console`

## Scenario
I'm trying to schedule a trigger for an API which I have written in Java and deployed in Lambda. Another purpose of this to avoid the cold start as I'm not using provisioned concurrency for my Lambda.
I'm not sure what event to pass so that my API gets triggered properly

## Expected behavior
I expect the API endpoint to be hit at a specific time and it should do what is implemented

## Actual behavior
Since I don't know what even to pass to my trigger so I'm gettings exceptions in my lambda cloudwatch logs

## Steps to reproduce
No code sample required, just create any Java-based Spring boot API on lambda and attach a scheduled cloudwatch event to it.
It will give exceptions in the cloudwatch logs.

## Full log output

```
2020-07-22 18:17:04.935 ERROR 1 --- [ main] c.a.s.proxy.AwsProxyExceptionHandler : Called exception handler for:
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "id" (class com.amazonaws.serverless.proxy.model.HttpApiV2ProxyRequest), not marked as ignorable (12 known properties: "requestContext", "rawQueryString", "body", "queryStringParameters", "isBase64Encoded", "routeKey", "version", "stageVariables", "rawPath", "cookies", "headers", "pathParameters"])
at [Source: (lambdainternal.util.NativeMemoryAsInputStream); line: 1, column: 22] (through reference chain: com.amazonaws.serverless.proxy.model.HttpApiV2ProxyRequest["id"])
at com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException.from(UnrecognizedPropertyException.java:61) ~[task/:na]
```

記録された HttpApiV2ProxyRequest のデシリアライズ失敗から始め、スケジュールされた AWS CloudWatch Events のペイロードと、Java Spring Boot Lambda 統合が想定するリクエスト形式を比較します。スケジュールされた呼び出しで報告された例外が発生しなくなり、意図した API の動作が行われれば完了です。

索引モデルが issue の本文から書いたものです。