patch 8.1.2398: strptime() test fails on Japanese Mac

Problem:    strptime() test fails on Japanese Mac.
Solution:   Use %T instead of %X.
diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index 7284787..6c4e813 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -231,7 +231,7 @@
   endif
   let $TZ = 'UTC'
 
-  call assert_equal(1484653763, strptime('%Y-%m-%d %X', '2017-01-17 11:49:23'))
+  call assert_equal(1484653763, strptime('%Y-%m-%d %T', '2017-01-17 11:49:23'))
 
   call assert_fails('call strptime()', 'E119:')
   call assert_fails('call strptime("xxx")', 'E119:')
diff --git a/src/version.c b/src/version.c
index f658039..0cb4bdd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2398,
+/**/
     2397,
 /**/
     2396,