Removed diff dates from rdiff files

mysql-test/suite/versioning/r/select,trx_id.rdiff

@@ -1,5 +1,5 @@
---- select.result	2018-06-29 18:09:17.962447067 +0200
-+++ select.reject	2018-06-29 18:10:04.618808616 +0200
+--- select.result
++++ select.reject
 @@ -17,6 +17,8 @@
  (8, 108),
  (9, 109);

mysql-test/suite/versioning/r/select2,trx_id.rdiff

@@ -1,5 +1,5 @@
---- select2.result	2018-06-29 17:51:17.142172085 +0200
-+++ select2,trx_id.reject	2018-06-29 18:03:49.034273090 +0200
+--- select2.result
++++ select2,trx_id.reject
 @@ -26,6 +26,8 @@
  select sys_start from t1 where x = 3 and y = 33 into @t1;
  Warnings:

mysql-test/suite/versioning/r/update,trx_id.rdiff

@@ -1,5 +1,5 @@
---- update.result	2018-12-19 13:55:35.873917389 +0300
-+++ update,trx_id.reject	2018-12-19 13:55:35.533917399 +0300
+--- update.result
++++ update,trx_id.reject
 @@ -81,12 +81,10 @@
  commit;
  select x, y, sys_trx_end = MAXVAL as current from t1 for system_time all order by sys_trx_end, x, y;