patch 8.2.0108: when sign text is changed a manual redraw is needed

Problem:    When sign text is changed a manual redraw is needed. (Pontus
            Lietzler)
Solution:   Redraw automatically. (closes #5455)
diff --git a/src/version.c b/src/version.c
index f15d748..e06dfc6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    108,
+/**/
     107,
 /**/
     106,