patch 8.2.4173: cannot use an import in 'foldexpr'

Problem:    Cannot use an import in 'foldexpr'.
Solution:   Set the script context to where 'foldexpr' was set. (closes #9584)
            Fix that the script context was not set for all buffers.
diff --git a/src/version.c b/src/version.c
index 45ae6d5..a9a8323 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4173,
+/**/
     4172,
 /**/
     4171,