patch 8.1.1901: the +insert_expand feature is not always available

Problem:    The +insert_expand feature is not always available.
Solution:   Graduate the +insert_expand feature.
diff --git a/src/version.c b/src/version.c
index 7dba139..b23da40 100644
--- a/src/version.c
+++ b/src/version.c
@@ -300,11 +300,7 @@
 #else
 	"-iconv",
 #endif
-#ifdef FEAT_INS_EXPAND
 	"+insert_expand",
-#else
-	"-insert_expand",
-#endif
 #ifdef FEAT_JOB_CHANNEL
 	"+job",
 #else
@@ -766,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1901,
+/**/
     1900,
 /**/
     1899,