patch 8.2.2151: $dir not expanded when configure checks for moonjit

Problem:    $dir not expanded when configure checks for moonjit.
Solution:   Use double quotes instead of single quotes. (closes #7478)
diff --git a/src/version.c b/src/version.c
index 86ccdd6..43daa6d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2151,
+/**/
     2150,
 /**/
     2149,