Fix CPack errors in Windows CI build

[dcwhite]

Interface_Application.vcxproj -> D:\a\SCIRun\SCIRun\bin\SCIRun\Release\Interface_Application.dll SCIRun.vcxproj -> D:\a\SCIRun\SCIRun\bin\SCIRun\Release\SCIRun.exe bundle_toolkit.vcxproj -> D:\a\SCIRun\SCIRun\bin\SCIRun\Release\bundle_toolkit.exe 1> CPack: Create package using NSIS CPack: Install projects CPack: - Install project: SCIRun [Release] CMake Error at D:/a/SCIRun/SCIRun/bin/SCIRun/Main/cmake_install.cmake:68 (file): file INSTALL cannot find "D:/a/SCIRun/Qt/5.15.2/msvc2019_64/lib/cmake/plugins/platforms/qwindows.dll": File exists. Call Stack (most recent call first): D:/a/SCIRun/SCIRun/bin/SCIRun/cmake_install.cmake:60 (include)