patch 8.2.3772: timer info test fails on slow machine

Problem:    Timer info test fails on slow machine.
Solution:   Use WaitForAssert().

src/testdir/test_timers.vim

@@ -121,8 +121,7 @@ func Test_timer_info()
   " check repeat count inside the callback
   let g:timer_repeat = []
   let tid = timer_start(10, {tid -> execute("call add(g:timer_repeat, timer_info(tid)[0].repeat)")}, #{repeat: 3})
-  sleep 100m
-  call assert_equal([2, 1, 0], g:timer_repeat)
+  call WaitForAssert({-> assert_equal([2, 1, 0], g:timer_repeat)})
   unlet g:timer_repeat
 endfunc
 

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3772,
 /**/
     3771,
 /**/