patch 8.2.2612: col('.') may get outdated column value

Problem:    col('.') may get outdated column value.
Solution:   Add a note to the help how to make this work and add a test for
            it. (closes #7971)
diff --git a/src/version.c b/src/version.c
index dad2038..815300c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2612,
+/**/
     2611,
 /**/
     2610,