Fix config problem

In the changes of PR AcademySoftwareFoundation#2584, set_and_check was the wrong macro to use
when the path might be empty -- because it is an error if the path
doesn't exist. The "check" part bites us. So just use a regular "set".

Signed-off-by: Larry Gritz <lg@larrygritz.com>

src/cmake/Config.cmake.in

@@ -9,7 +9,7 @@ include(CMakeFindDependencyMacro)
 set_and_check (@PROJECT_NAME@_INCLUDE_DIR "@CMAKE_INSTALL_FULL_INCLUDEDIR@")
 set_and_check (@PROJECT_NAME@_INCLUDES    "@CMAKE_INSTALL_FULL_INCLUDEDIR@")
 set_and_check (@PROJECT_NAME@_LIB_DIR     "@CMAKE_INSTALL_FULL_LIBDIR@")
-set_and_check (@PROJECT_NAME@_PLUGIN_SEARCH_PATH         "@PLUGIN_SEARCH_PATH_NATIVE@")
+set (@PROJECT_NAME@_PLUGIN_SEARCH_PATH         "@PLUGIN_SEARCH_PATH_NATIVE@")
 
 #...logic to determine installedPrefix from the own location...
 #set (@PROJECT_NAME@_CONFIG_DIR  "${installedPrefix}/@CONFIG_INSTALL_DIR@")