[FEATURE] Add validation to ensure that events are created based on the specified schema

[sandeep-ps]

Is your feature request related to a problem? Please describe.
We don't have validation enabled on event data apart from the required fields. Though this gives flexibility to the client applications, it also gives less control over the data stored by the Events Building Block.

Describe the solution you'd like
Enable validation to ensure that all incoming event data follows the specified schema. It's possible that the schema may need to be updated to accommodate some of the custom attributes coming from different client applications.

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

Additional context
We are excluding all-day events from the system. To enforce such changes, the Events Building Block must validate the incoming event data.