i18n (check-text) returning false positives

**Config:**
```JSON
{
"rules": {
"i18n": [
true,
"check-id",
"check-text"
]
}
}
```

```ts
@Component({
template: `

add



visibility{{ passwordType === 'text' ? '_off' : '' }}


`
})
class Test {}
```

Reproduce the reported i18n check-text failures with the supplied Angular template and configuration. Start at the i18n rule's check-text handling, then compare its treatment of mat-icon text and the interpolated password icon expression. Done means these examples no longer produce false-positive reports.

Written by the indexing model from the issue text.