can't map prefixed address with query string

Using `import_map.json`
```
{
"imports": {
"icons-solid-20/": "https://esm.sh/@heroicons/react@2.0.11/20/solid/?alias=react:preact/compat"
}
}
```
With script:
```
import 'icons-solid-20/BeakerIcon';
```
Will yield error:
```
Import map diagnostics:
- Invalid target address "https://esm.sh/@heroicons/react@2.0.11/20/solid/?alias=react:preact/compat" for package specifier "icons-solid-20/". Package address targets must end with "/".
error: Blocked by null entry for ""icons-solid-20/""
```

Even when putting in a bogus query parameter that ends with "/", the following error is produced:
```
error: The specifier ""icons-solid-20/BeakerIcon"" backtracks above its prefix ""icons-solid-20/""
```