patch 8.1.1893: script to summarize test results can be improved

Problem:    Script to summarize test results can be improved.
Solution:   Use "silent" for substitute to avoid reporting number of matches.
            Remove duplicate "set nocp". (Daniel Hahler, closes #4845)
diff --git a/src/version.c b/src/version.c
index 5d802fd..b7ceb36 100644
--- a/src/version.c
+++ b/src/version.c
@@ -766,6 +766,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1893,
+/**/
     1892,
 /**/
     1891,