Error Response when no matching functions

[prsh9]

Description

Send response to indicate no matching functions are found for the topic.

Motivation and Context

Currently when invoking a function on a topic with controller.Invoke() and there are no matching functions (probably due to function still being loaded, topic-map not refreshed) there is no way to acknowledge upstream. Consider using amqp which uses manual auto-ack, there is no way to determine the failure and do a negative ack / track such invocation failure.

Fixes issue #61

• [x] I have raised an issue to propose this change (required)
• [ ] My issue has received approval from the maintainers or lead with the design/approved label

How Has This Been Tested?

Performed manual testing and recorded the behaviour.

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I've read the CONTRIBUTION guide
• [x] I have signed-off my commits with git commit -s
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.

[derek[bot]]

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