This avoids cyclic subproject configuration when the 'harfbuzz' feature is
enabled, or `--wrap-mode=forcefallback` is used, but HarfBuzz is built as a
subproject. HarfBuzz does the same and disables HarfBuzz support when
configuring FreeType as a subproject.
* meson.build (harfbuzz_dep): Implement it.
* subprojects/harfbuzz.wrap: New file.
* .gitlab-ci.yml [windows meson]: Use latest version of the meson 0.59
series, which has a necessary bug fix to make CI work.
