Support kafka trigger

I was unable to find documentation how to configure the librdkafka settings in JS with the v4 runtime.

1. How can we configure properties such as `AutoOffsetReset`/`auto.offset.reset`?
2. Is there a types package that we can leverage to type the options since there is no `kafka` specific trigger and we must use the `generic` trigger?

Thank you in advance for your insight

#### Investigative information

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- Timestamp: N/A
- Function App name: N/A
- Function name(s) (as appropriate): N/A
- Invocation ID: N/A
- Region: N/A

#### Repro steps

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#### Expected behavior

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#### Actual behavior

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#### Known workarounds

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#### Related information

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* Programming language used : Typescript
* Links to source
* Bindings used: Kafka
* Runtime: "@azure/functions": "^4.0.1",
* `host.json`:
```json
{
"version": "2.0",
"logging": {
"applicationInsights": {
"samplingSettings": {
"isEnabled": true,
"excludedTypes": "Request"
}
}
},
"extensionBundle": {
"id": "Microsoft.Azure.Functions.ExtensionBundle",
"version": "[4.*, 5.0.0)"
}
}
```