[DOCUMENTATION] Complete the example for sending relays

[adshmh]

Objective

Following the refactoring of the SDK, most recently in PR #15, it seems very helpful to have a complete example to guide the users in using the SDK for sending relays.

Origin Document

Here is a snapshot of a code snippet from relay_test.go which shows a generally correct, but incomplete example of how to send a relay request using the SDK:

Goals

• Complete the above example
• Update any comments as needed, more specifically target the godoc generated document.

Deliverables

• Updated example for sending a relay (in relay_test.go)
• Updated comments on functions/components involved in the above example.
• ...

General deliverables

• Comments: Add/update TODOs and comments alongside the source code so it is easier to follow.
• Testing: Add new tests (unit and/or E2E) to the test suite.
• Documentation: Update architectural or development READMEs; use mermaid diagrams where appropriate.

Creator: [adshmh]

[red-0ne]

Closed as per #15 and #19