Add Japanese translations - guides/index.ja.md, labs/index.ja.md

[Norio4]

Author checklist (to be completed by original Author)

• Is this document a good fit for the Rocky project ?
• Is this a non-English contribution?
• Title and Author MetaTags have been inserted into the document
• If applicable, steps and instructions have been tested to work on a real system
• Did you perform an initial self-review to fix basic typos and grammatical correctness

Rocky Documentation checklist (to be completed by Rocky team)

• 1st Pass (Check that document is good fit for project and author checklist completed)
• 2nd Pass (Technical Review - check for technical correctness)
• 3rd Pass (Basic Editorial Review)
• 4th Pass (Detailed Editorial Review and Peer Review)
• 5th Pass (Include document in TOC)
• Final pass/approval (Final Review)

[sspencerwire]

@Norio4 no need to keep "Home" in the "Guides Home" ... was that your intent? I can hold off if you want to push a change. For example, this:

---
title: ガイド Home
---

can be:

---
title: ガイドホーム
---

The only time when the English needs to be preserved is when we are dealing with the top-level menu OR the README.md. I'll wait to see if you push a change. Otherwise it looks good! Thanks, Steve

[Norio4]

@sspencerwire Thank you for your revewing my pr.
I've changed "Guide Home" to "ガイド・ホーム".

Thank you.