'amp-google-document-embed' doesn't always load embedded documents

### Description

Using 'amp-google-document-embed' to embed multiple documents on a single page does not always work, sometimes the loader crashes

### Reproduction Steps

I'm working with Statamic v3, add the following code to a page and reload the page a few times
```

```

### Relevant Logs

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### Browser(s) Affected

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### OS(s) Affected

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### Device(s) Affected

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### AMP Version Affected

_No response_