Add @lisaxiao299-maker to CONTRIBUTORS.md

[lisaxiao299-maker]

Adding my name to the contributors list as part of bounty task #441

[github-actions]

Welcome to RustChain! Thanks for your first pull request.

Before we review, please make sure:

• Your PR has a BCOS-L1 or BCOS-L2 label
• New code files include an SPDX license header
• You've tested your changes against the live node

Bounty tiers: Micro (1-10 RTC) | Standard (20-50) | Major (75-100) | Critical (100-150)

A maintainer will review your PR soon. Thanks for contributing!

[Scottcjn]

Closing — the CONTRIBUTORS.md file is for people who have made a code or documentation contribution to RustChain. Adding your name without a prior contribution does not qualify for bounty #441.

Here is how to earn your spot:

1. Pick an open bounty from https://github.com/Scottcjn/rustchain-bounties
2. Submit a PR with real code or docs
3. Once merged, add yourself to CONTRIBUTORS.md in the same PR or a follow-up

We would love to have you contribute! Start with a small bounty and work your way up.