Implement maximum message size exceeded check for MS Teams.

[progala]

Environment

• Nautobot version: 1.0.2+
• nautobot-plugin-chatops version: 1.5.1

Proposed Functionality

Proposal is to add a new setting "MICROSOFT_MAX_MSG_SIZE" that would be used to check if the prepared content exceeds the provided value.

If the size of the prepared content exceeds the specified value, then the error message would be sent to MS Teams chat and an warning would be logged internally.

Use Case

When number of objects is large response generated by some of the chatbot commands exceed maximum allowed message size in MS Teams.

The problem is that Nautobot emits a message but the message never makes it to MS Teams. Ocasionally part of the response, like reponse header, might be received, with the rest of the message not showing up in the chat. This represents a silent failure that makes it difficult to debug and reason about, i.e. it's not apparent to the end user what, if anything, is wrong.