patch 8.1.1972: no proper test for getchar()

Problem:    No proper test for getchar().
Solution:   Add a test with special characters.
diff --git a/src/version.c b/src/version.c
index 85526b6..321da51 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1972,
+/**/
     1971,
 /**/
     1970,