patch 8.2.2556: Vim9: :import with "as" not fully supported

Problem:    Vim9: :import with "as" not fully supported.
Solution:   Implement "as" for more cases.
diff --git a/src/version.c b/src/version.c
index 1dfd0d6..d6065b7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2556,
+/**/
     2555,
 /**/
     2554,