api: Exclude None values from request payload in Endpoint class.

[octocamocoder47]

Description
Refactored the Endpoint class to exclude parameters with None values from the request payload. This ensures cleaner API interactions and avoids unintended behavior, improving code reliability and alignment with best practices.

Fixes: #847 (#847 )

How did you test this PR?

I couldn't test PR because I don't have api keys and proper env setup to test it.

• Self-reviewed the changes for clarity and maintainability
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[timabbott]

@Niloth-p I assume you'll take point on reviewing this.