Add data lifecycle links to quickstarts

[kilfoyle]

In a review of the ILM docs it was requested that we add links to those docs from various quickstarts, etc.

Rel: #1568

As part of that, this PR adds a link at the end of security SIEM and endpoint security tutorials:

---

Please see previews:

• SIEM tutorial next steps
• endpoint security next steps

[github-actions]

🔍 Preview links for changed docs

• solutions/security/get-started/get-started-detect-with-siem.md
• solutions/security/get-started/get-started-endpoint-security.md

[nastasha-solomon]

lgtm!