This reverts commit 9ca7ba8.

Reverts #27844. This change broke the pipeline, pacmak fails with:

```
#STDOUT> /tmp/npm-packu6YRYj/Amazon.CDK.IntegTests.Alpha/Amazon/CDK/IntegTests/Alpha/ApiCallBase.cs(231,77): error CS0115: 'ApiCallBase._Proxy.WaiterProvider': no suitable method found to override [/tmp/npm-packu6YRYj/Amazon.CDK.IntegTests.Alpha/Amazon.CDK.IntegTests.Alpha.csproj]
```

This PR changes to add the `waiterProvider` property to an `IApiCall` for `awsApiCall` in integ-tests-alpha.

By default `awsApiCall` in integ tests, the AwsApiCall construct will automatically add the correct IAM policies to allow the Lambda function to make the API call. It does this based on the service and api that is provided. In the following example the service is SQS and the api is receiveMessage so it will create a policy with Action: 'sqs:ReceiveMessage'.

```ts
const integ = new IntegTest(app, 'Integ', {
  testCases: [stack],
});
integ.assertions.awsApiCall('SQS', 'receiveMessage', {
  QueueUrl: 'url',
});
```

There are some cases where the permissions do not exactly match the service/api call, for example the S3 listObjectsV2 api. In these cases it is possible to add the correct policy by accessing the `provider` object.

```ts
const apiCall = integ.assertions.awsApiCall('S3', 'listObjectsV2', {
  Bucket: 'mybucket',
});

apiCall.provider.addToRolePolicy({
  Effect: 'Allow',
  Action: ['s3:GetObject', 's3:ListBucket'],
  Resource: ['*'],
});
```

On the other hand, there is the case to use `waitForAssertions` when using `awsApiCall` in integ tests. This causes `apiCall` to have a `waiterProvider` property in addition to `provider`.

```ts
const apiCall = integ.assertions.awsApiCall('S3', 'listObjectsV2', {
  Bucket: 'mybucket',
}).expect(ExpectedResult.objectLike({
  KeyCount: 1,
})).waitForAssertions({
  interval: cdk.Duration.seconds(30),
  totalTimeout: cdk.Duration.minutes(10),
});
```

In the case, `waiterProvider` actually calls to the service/api, so it should have the proper policies.

However a type of a return value of `apiCall` is `IApiCall` interface so that the interface has a `provider` property, `waiterProvider` is not in `IApiCall` but in `AwsApiCall`.

Then it cannot take the policies without casting the following. (`apiCall instanceof AwsApiCall`)

```ts
if (apiCall instanceof AwsApiCall) {
  apiCall.waiterProvider?.addToRolePolicy({
    Effect: 'Allow',
    Action: ['s3:GetObject', 's3:ListBucket'],
    Resource: ['*'],
  });
}
```

So I add `waiterProvider` to `IApiCall`, so that it can take the policies without casting:

```ts
// if (apiCall instanceof AwsApiCall) {
  apiCall.waiterProvider?.addToRolePolicy({
    Effect: 'Allow',
    Action: ['s3:GetObject', 's3:ListBucket'],
    Resource: ['*'],
  });
//}
```

In my opinion, I see no negative impact from this.

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Reverts aws#27844. This change broke the pipeline, pacmak fails with:

```
#STDOUT> /tmp/npm-packu6YRYj/Amazon.CDK.IntegTests.Alpha/Amazon/CDK/IntegTests/Alpha/ApiCallBase.cs(231,77): error CS0115: 'ApiCallBase._Proxy.WaiterProvider': no suitable method found to override [/tmp/npm-packu6YRYj/Amazon.CDK.IntegTests.Alpha/Amazon.CDK.IntegTests.Alpha.csproj]
```