patch 8.2.2704: adding a lot of completions can be a bit slow

Problem:    Adding a lot of completions can be a bit slow.
Solution:   Use fast_breakcheck() instead of ui_breakcheck() when adding a
            list of completions. (Ben Jackson, closes #8061)
diff --git a/src/version.c b/src/version.c
index 812b1e5..b557d59 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2704,
+/**/
     2703,
 /**/
     2702,