[Intermediate]: exclude team posts when triggering .github/scripts/bot-gfi-assign-on-comment.js

[exploreriii]

🧩 Intermediate Contributors

This issue is intended for contributors who already have some familiarity with the
Hiero Python SDK codebase and contribution workflow.

You should feel comfortable:

• navigating existing source code and examples
• understanding SDK concepts without step-by-step guidance
• following the standard PR workflow without additional onboarding

If this is your very first contribution to the project, we recommend starting with a few
Good First Issues before working on this one.

🐞 Problem Description

Team posts on a good first issue may trigger this message:

function buildAssignReminder(username) {
return `${ASSIGN_REMINDER_MARKER}
👋 Hi @${username}!

If you’d like to work on this Good First Issue, just comment:

```
/assign
```

and you’ll be automatically assigned. Feel free to ask questions here if anything is unclear!`;
}

We should not send the message if the user is a team member

💡 Expected Solution

add an exclusion restriction is team member and skip if that's the case

🧠 Implementation Notes

Might be part of a bigger refactor

✅ Acceptance Criteria

To merge this issue, the pull request must:

• Fully address the problem described above
• Follow existing project conventions and patterns
• Include tests or example updates where appropriate
• Pass all CI checks
• Include a valid changelog entry
• Use DCO and GPG-signed commits

📚 Additional Context or Resources

• SDK Developer Docs
• SDK Developer Training

[exploreriii]

Temporarily reopened fresh - not feasible to close quickly in the refactor i had planned