🐛 Google Analytics 4 Related Bug:

### Description

GA4 events do not include custom event parameters that are defined in the config. According to [this documentation](https://developers.google.com/analytics/devguides/collection/amp-analytics#modify_parameters), I would expect custom parameters to show up in the events. The behavior I've noticed is that the parameters in the config that are overriding google's default parameters (such as "page_title") show up across all events as expected. But the parameters in the config that are new/custom to our usage (such as "content_id") do not show up across all events and are only in the `page_view` event. I was able to reproduce this issue in the amp playground link provided.

You can see in the `page_view` event, `dt` and `ep.content_id` are in the payload as expected.

However, in the `h1 click` event, only `dt` is in the payload and not `ep.content_id`.

### URL where we can debug and reproduce the problem

https://playground.amp.dev/#share=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

### Reproduction Steps

With the following GA4 AMP configuration, inspect the payload for the `page_view` event and the `h1 click` event and you will notice `content_id` is included in the `page_view` but missing from `h1 click`.

`

{
"vars": {
"config": {
"G-1111": {
"content_id": "12345",
"page_title": "Hello World 123"
}
}
},
"triggers": {
"h1_click": {
"on": "click",
"selector": "h1",
"vars": {
"event_name": "h1 click"
}
}
}
}

`

### Relevant Logs

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### Browser(s) Affected

_No response_

### OS(s) Affected

_No response_

### Device(s) Affected

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### AMP Version Affected

_No response_