patch 8.2.2571: test may leave file behind

Problem:    Test may leave file behind.
Solution:   Delete the temporary file.  Don't profile in the running Vim
            instance.
diff --git a/src/testdir/test_quickfix.vim b/src/testdir/test_quickfix.vim
index 6ade326..6f25f1d 100644
--- a/src/testdir/test_quickfix.vim
+++ b/src/testdir/test_quickfix.vim
@@ -5362,4 +5362,14 @@
   call Xqfbuf_update('l')
 endfunc
 
+func Test_vimgrep_noswapfile()
+  set noswapfile
+  call writefile(['one', 'two', 'three'], 'Xgreppie')
+  vimgrep two Xgreppie
+  call assert_equal('two', getline('.'))
+
+  call delete('Xgreppie')
+  set swapfile
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab