Fix building UMF via FetchContent

Fix "cmake_uninstall.cmake.in does not exist"

Author: igchor

CMakeLists.txt

@@ -173,9 +173,9 @@ install(
     DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME})
 
 configure_file(
-    "${CMAKE_SOURCE_DIR}/cmake/cmake_uninstall.cmake.in"
-    "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake"
+    "${PROJECT_SOURCE_DIR}/cmake/cmake_uninstall.cmake.in"
+    "${PROJECT_BINARY_DIR}/cmake_uninstall.cmake"
     IMMEDIATE @ONLY)
 
 add_custom_target(uninstall
-    COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake)
+    COMMAND ${CMAKE_COMMAND} -P ${PROJECT_BINARY_DIR}/cmake_uninstall.cmake)