add parameter to override bot name

[oussa]

closes #138

Success criteria

• Overriding bot name during chat using botAvatarNameOverride like this:

{
  "_webchat": {
    "botAvatarNameOverride": "Bob"
  }
}

How to test

Create a flow on Cognigy. Add a Say node and specify in the options the above example config. Then test the endpoint and see the bot name being overridden.

Security

• Possible injection vector
• Authentication/Access controls touched
• Sensitive Data could be exposed
• XSS
• Logging/Monitoring touched
• Exchanges data with external systems
• No security implications