install(EXPORT ..) for different build types removes previous installed Targets file
When using the install(EXPORT …) task a Targets-Release or Targets-Debug etc is generated/installed, depending on the build type. But when installing a next build type, the files for the first build type are always removed. So I always end up with either a Targets-Release, or Targets-Debug, etc and not multiple.
Currently this makes it impossible to do an installation for multiple build types.