docs: add Gobyexample under Go category

[sharvandeep]

Closes: #1792

What I changed

• Added Gobyexample resource under the Go category in data.json.

Why this change?

The original Gobyexample entry was missing, and this resource is widely recommended for beginners to learn Go using short annotated examples.

How I tested

• Verified valid JSON formatting.
• Confirmed correct link formatting.

Checklist:

• I followed CONTRIBUTING.md
• Only data/documentation updated

[sharvandeep]

Hi 👋

This PR adds the missing Gobyexample link under the Go category — a helpful learning resource for beginners. It closes #1792 and follows the formatting and contribution guidelines.

Appreciate a review and merge when convenient

cc @MunGell