Update User Profiles retention to reflect Product Analytics extension (#35820)

* Update User Profiles retention to reflect Product Analytics extension

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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* Apply suggestions from code review

Co-authored-by: Ida Adjivon <65119712+iadjivon@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Ida Adjivon <65119712+iadjivon@users.noreply.github.com>

* Apply suggestion from @iadjivon

* Apply suggestion from @iadjivon

* Apply suggestion from @iadjivon

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: jeff-morgan-dd <jeff.morgan@datadoghq.com>

Author: 3 people

content/en/data_security/data_retention_periods.md

@@ -137,7 +137,7 @@ attributes:
   - product: Product Analytics
     data_type: |
        - **Events**: 15 months
-       - **User Profiles**: 30 days
+       - **User Profiles**: 15 months, or 30 days if <a href="/product_analytics/guide/rum_and_product_analytics/#how-do-i-set-up-product-analytics">Product Analytics is not enabled</a>
   - product: PR Gates
     data_type: |
        - **Gate evaluations**: 30 days
@@ -175,3 +175,4 @@ attributes:
 ### Further Reading
 
 {{< partial name="whats-next/whats-next.html" >}}
+