Merge topic 'cmStringAlgorithms_modernize'

4aa555f9da Tests: Add CMakeLib.testStringAlgorithms test
75cf7ec263 cmStringAlgorithms: Modernize cmWrap using cm::string_view
e5d3ea22d4 cmStringAlgorithms: Add cmCatViews and cmStrCat functions
a7d0fe9c24 cmStringAlgorithms: Simplify cmJoin using cm::string_view
541361a58b cmStringAlgorithms: Simplify cmStrCmp using cm::string_view

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !3628