patch 8.2.0533: tests using term_wait() can still be flaky

Problem:    Tests using term_wait() can still be flaky.
Solution:   Increase the wait time when rerunning a test. (James McCoy,
            closes #5899)  Halve the initial times to make tests run faster
            when there is no rerun.
diff --git a/src/testdir/test_terminal_fail.vim b/src/testdir/test_terminal_fail.vim
index f33ade6..d621d03 100644
--- a/src/testdir/test_terminal_fail.vim
+++ b/src/testdir/test_terminal_fail.vim
@@ -10,7 +10,7 @@
 func Test_terminal_redir_fails()
   if has('unix')
     let buf = term_start('xyzabc', {'err_io': 'file', 'err_name': 'Xfile'})
-    call term_wait(buf)
+    call TermWait(buf)
     call WaitFor('len(readfile("Xfile")) > 0')
     call assert_match('executing job failed', readfile('Xfile')[0])
     call WaitFor('!&modified')