Help: Fix typo in cmake-buildsystem(7) manual

repeated word:

... of a shared shared library target created ...

Topic-rename: cmake-buildsystem-manual-typo

assigned to @craig.scott

changed milestone to %3.13.0

added area:doc label

changed the description

Do: stage

added workflow:nightly-testing label

Thanks for the cleanup.

Do: merge

removed workflow:nightly-testing label

mentioned in commit 3f589678

merged