🐛 Google Analytics 4 Related Bug: Virtual pageview in gtag with both UA e GA4 configured

### Description

Hi, i have configured both UA e GA4 inside amp_analytics type=gtag and it seems to send the correct pageview to both properties on the first load, is it possible to send a virtual page view identical to the first one using triggers? In my example i can only send an event which is probably fine for GA4 but it's not accepted as pageview inside the UA dashboard

`

{
"vars": {
"gtag_id": "UA-1111",
"config": {
"UA-1111": {
"groups": "default",
"custom_map": {
"dimension1": "dim1"
},
"dim1": "testampgtagdimension"
},
"G-1111": {
"groups": "default",
"dimension1": "testampgtagdimension"
}
}
},
"triggers": {
"virtualpage": {
"on": "click",
"selector": "#tasto",
"vars": {
"event_name": "page_view"
}
}
}
}

`

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

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

### Reproduction Steps

* click on the test button to send the event

### Relevant Logs

_No response_

### Browser(s) Affected

_No response_

### OS(s) Affected

_No response_

### Device(s) Affected

_No response_

### AMP Version Affected

_No response_