patch 8.1.2364: termwinscroll test is flaky on FreeBSD

Problem:    Termwinscroll test is flaky on FreeBSD.
Solution:   Add to list of flaky tests.  Rename function.
diff --git a/src/testdir/runtest.vim b/src/testdir/runtest.vim
index c05bd25..9372d53 100644
--- a/src/testdir/runtest.vim
+++ b/src/testdir/runtest.vim
@@ -3,7 +3,7 @@
 " Errors are appended to the test.log file.
 "
 " To execute only specific test functions, add a second argument.  It will be
-" matched against the names of the Test_ funtion.  E.g.:
+" matched against the names of the Test_ function.  E.g.:
 "	../vim -u NONE -S runtest.vim test_channel.vim open_delay
 " The output can be found in the "messages" file.
 "
@@ -365,6 +365,7 @@
       \ 'Test_terminal_wall()',
       \ 'Test_terminal_wipe_buffer()',
       \ 'Test_terminal_wqall()',
+      \ 'Test_termwinscroll()',
       \ 'Test_timer_oneshot()',
       \ 'Test_timer_paused()',
       \ 'Test_timer_repeat_many()',