[Good First Issue]: Update developer-guide.md

[mustafauzunn]

🆕🐥 First Timers Only

This issue is reserved for people who have never contributed or have made minimal contributions to Hiero.
We know that creating a pull request (PR) is a major barrier for new contributors.
The goal of this issue and all other issues in find a good first issue is to help you make your first contribution to the Hiero.

👾 Description of the issue

There is a mistake in https://github.com/hiero-ledger/hiero-sdk-java/blob/main/docs/sdk/developer-guide.md.
On line 130 under Updating proto files section ./gradlew updateSnapshots must be ./gradlew updateProto

💡 Proposed Solution

On line 130 in developer-guide.md ./gradlew updateSnapshots change to ./gradlew updateProto.

Also add note "checkout_ref variable in update_protobufs.py should be updated with the version with needed protobufs before running the command"

👩‍💻 Implementation Steps

On line 130 in developer-guide.md ./gradlew updateSnapshots change to ./gradlew updateProto

Also add note "checkout_ref variable in update_protobufs.py should be updated with the version with needed protobufs before running the command"

✅ Acceptance Criteria

To be able to merge a pull request for this issue, we need:

• Signed commits: commits must be DCO and GPG key signed
• All Tests Pass: our workflow checks like unit and integration tests must pass
• Issue is Solved: The implementation fully addresses the issue requirements as described above
• No Further Changes are Made: Code review feedback has been addressed and no further changes are requested

📋 Step-by-Step Contribution Guide

If you have never contributed to an open source project at GitHub, the following step-by-step guide will introduce you to the workflow.
More information and concrete samples for shell commands for each step can be found in our CONTRIBUTING.md file.
A more detailed general documentation of the GitHub PR workflow can be found here.

• Claim this issue: Comment below that you are interested in working on the issue
• Wait for assignment: A community member with the given rights will add you as an assignee of the issue
• Work on the issue: Follow the detailed description in our CONTRIBUTING.md file.
• You did it 🎉: We will merge the fix in the main branch. Thanks for being part of the Hiero community as an open-source contributor!

IMPORTANT Your pull request CANNOT BE MERGED until your commits are each with git commit -S -s -m "chore: your commit message" with a GPG key setup.

🤔 Additional Information

If you have any questions about the topic of this issue, please ask us directly by adding a comment below.
Additionally, we invite you to join our community on our Discord server or attend our public community calls.

A general manual about open-source contributions can be found here.

---

[brutalsachin]

Hi, I would like to work on this issue. Can you assign it to me?

[Naveenjaikumar]

Hii, I'd like to work on this issue. The changes are clear and I can implement them as described.