Fix test cases whose behavior differs when their source or build tree is
under CMAKE_INSTALL_PREFIX by setting an install prefix under the build
tree. Otherwise they may fail when run under the default install prefix
(e.g. /usr/local).
The moved tests are related to paths in INTERFACE_INCLUDE_DIRECTORIES
in general, and when exporting, and covering cases of the install
location being within the build or source prefix etc. Other build
properties containing paths should have similar tests, so this
allows some parameterization while keeping the preparation of the
various directory structures.