patch 8.2.3664: cannot adjust sign highlighting for 'cursorline'

Problem:    Cannot adjust sign highlighting for 'cursorline'.
Solution:   Add CursorLineSign and CursorLineFold highlight groups.
            (Gregory Anders, closes #9201)
diff --git a/src/highlight.c b/src/highlight.c
index 77ad0bc..fe4f089 100644
--- a/src/highlight.c
+++ b/src/highlight.c
@@ -153,6 +153,8 @@
     "lCursor guibg=fg guifg=bg", // should be different, but what?
 #endif
     "default link QuickFixLine Search",
+    "default link CursorLineSign SignColumn",
+    "default link CursorLineFold FoldColumn",
     CENT("Normal cterm=NONE", "Normal gui=NONE"),
     NULL
 };