Merge topic 'FindRuby-restore-include-path' into release-3.18

6959744131 FindRuby: Restore compatibility variable RUBY_INCLUDE_PATH

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !5109
diff --git a/Modules/FindRuby.cmake b/Modules/FindRuby.cmake
index 1bdee60..3b8122e 100644
--- a/Modules/FindRuby.cmake
+++ b/Modules/FindRuby.cmake
@@ -50,7 +50,7 @@
 
 Also:
 
-``Ruby_INCLUDE_PATH``
+``RUBY_INCLUDE_PATH``
   same as Ruby_INCLUDE_DIRS, only provided for compatibility reasons, don't use it
 
 Hints
@@ -493,7 +493,6 @@
     Ruby_VERSION_MAJOR
     Ruby_VERSION_MINOR
     Ruby_VERSION_PATCH
-    Ruby_INCLUDE_PATH
 
     Ruby_ARCH_DIR
     Ruby_ARCH