doc: fix the version for a chapter

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2 jobs for master in 30 minutes and 11 seconds (queued for 34 minutes and 46 seconds)
Status Job ID Name Coverage
  Build
passed #74930
build_clazy_clang_tidy

00:17:55

passed #74929
linux kf5-qt5 qt5.12

00:12:15

11.0%