Add "Source" cases to "Dialogflow" connector

[M-Shorouk]

Is your feature request related to a problem? Please describe.

Currently, Dialogflow as a connector is only reading from "Airy Chat Plugin". As an Airy user, i need to enable Dialogflow when installed on all my "Active" connected sources connected to Airy.

Describe the solution you'd like

1. Add the following case switch to read different sources Metadata ondialogflow-connector:

if (text != "") {
final ObjectNode node = getNode();
switch (source) {
case "google": {
final ObjectNode representative = getNode();
representative.put("representativeType", "BOT");
node.set("representative", representative);
node.put("text", text);
return mapper.writeValueAsString(node);
}
case "viber": {
node.put("text", text);
node.put("type", "text");
return mapper.writeValueAsString(node);
}
case "chatplugin":
case "instagram":
case "facebook": {
node.put("text", text);
return mapper.writeValueAsString(node);
}
case "twilio.sms":
case "twilio.whatsapp": {
node.put("Body", text);
return mapper.writeValueAsString(node);
}
case "whatsapp": {
node.put("Body", text);
return mapper.writeValueAsString(node);
}
default: {
return null;
}
}
}

## Describe alternatives you've considered

A clear and concise description of any alternative solutions or features you've considered.

## Additional context

Add any other context or screenshots about the feature request here.

[M-Shorouk]

@AitorAlgorta can we do this one? I think @AudreyKj created the library for these sources where i assume is easy to add to the connector?

Also this is the DOCS update ticket

[AudreyKj]

@M-Shorouk @AitorAlgorta The library for the sources has been merged, and it's not a lot of work to add this lib to the Dialogflow connector. However, it testing Dialogflow + all the sources would take a lot of time. So not sure we will have time to do this ticket before the release next week.

[M-Shorouk]

@AudreyKj i think we were done with the source library.. can we quickly do this ticket before the release?