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_cmdline.vim b/src/testdir/test_cmdline.vim
index e2b7fc2..8aabaa8 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -947,7 +947,7 @@
   call writefile(lines, 'XTest_verbose')
 
   let buf = RunVimInTerminal('-S XTest_verbose', {'rows': 12})
-  call term_wait(buf, 100)
+  call TermWait(buf, 50)
   call term_sendkeys(buf, ":DoSomething\<CR>")
   call VerifyScreenDump(buf, 'Test_verbose_option_1', {})
 
@@ -1024,7 +1024,7 @@
   call writefile(lines, 'XTest_restore')
 
   let buf = RunVimInTerminal('-S XTest_restore', {'rows': 12})
-  call term_wait(buf, 100)
+  call TermWait(buf, 50)
   call term_sendkeys(buf, "q:")
   call VerifyScreenDump(buf, 'Test_cmdwin_restore_1', {})
 
@@ -1146,7 +1146,7 @@
 
   call writefile(lines, 'XtestCmdlineClearTabenter')
   let buf = RunVimInTerminal('-S XtestCmdlineClearTabenter', #{rows: 10})
-  call term_wait(buf, 50)
+  call TermWait(buf, 25)
   " in one tab make the command line higher with CTRL-W -
   call term_sendkeys(buf, ":tabnew\<cr>\<C-w>-\<C-w>-gtgt")
   call VerifyScreenDump(buf, 'Test_cmdlineclear_tabenter', {})