[API Creation] Create API fails with HTTP 500 without giving any information.

[slahirucd7]

Description

Hi Team,

API creation fails with HTTP 500 without giving any informative error.
This happens due to creating APIs with existing name and existing context.

But error message is not clearly stating that.

Steps to reproduce:

Scenario 1

1. Create an API with a name.
2. Create an API with same name but with different context. API creation gives HTTP 500.

Scenario 2

1. Create an API with a context.
2. Create an API with same context but with different name. API creation gives HTTP 500.

Need to handle above two scenarios with proper error messages.

[thivindu]

This will be fixed via future enhancements to the PR - #173