Frameworks announcements: Add missing qtVersion

CCMAIL: faure@kde.org

content/announcements/frameworks/5/5.86.0.md

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-qtversion: 
+qtversion: 5.15.2
 date: 2021-09-11
 layout: framework
 libCount: 83

content/announcements/frameworks/5/5.87.0.md

 ---
-qtversion: 
+qtversion: 5.15.2
 date: 2021-10-09
 layout: framework
 libCount: 83

content/announcements/frameworks/5/5.88.0.md

 ---
-qtversion: 
+qtversion: 5.15.2
 date: 2021-11-13
 layout: framework
 libCount: 83

content/announcements/frameworks/5/5.89.0.md

 ---
-qtversion: 
+qtversion: 5.15.2
 date: 2021-12-11
 layout: framework
 libCount: 83

content/announcements/frameworks/5/5.90.0.md

 ---
-qtversion: 
+qtversion: 5.15.2
 date: 2022-01-08
 layout: framework
 libCount: 83

content/announcements/frameworks/5/5.91.0.md

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-qtversion: 
+qtversion: 5.15.2
 date: 2022-02-13
 layout: framework
 libCount: 83