patch 8.0.1267: Test_swap_group may leave file behind

Problem:    Test_swap_group may leave file behind.
Solution:   Add a try/finally.

src/testdir/test_swap.vim

@@ -56,6 +56,7 @@ func Test_swap_group()
     throw 'Skipped: need at least two groups, got ' . string(groups)
   endif
 
+  try
     call delete('Xtest')
     split Xtest
     call setline(1, 'just some text')
@@ -77,6 +78,7 @@ func Test_swap_group()
 	bwipe!
       endif
     endif
-
+  finally
     call delete('Xtest')
+  endtry
 endfunc

src/testdir/test_undo.vim

@@ -190,6 +190,7 @@ func Test_undojoin_redo()
 endfunc
 
 func Test_undo_write()
+  call delete('Xtest')
   split Xtest
   call feedkeys("ione one one\<Esc>", 'xt')
   w!

src/version.c

@@ -761,6 +761,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1267,
 /**/
     1266,
 /**/