patch 8.1.0693: channel test fails sometimes

Problem:    Channel test fails sometimes.
Solution:   Avoid race condition.

Author: brammool

src/testdir/test_channel.vim

@@ -1650,17 +1650,16 @@ func Test_write_to_deleted_buffer()
     return
   endif
   let job = job_start('echo hello', {'out_io': 'buffer', 'out_name': 'test_buffer', 'out_msg': 0})
-  call WaitForAssert({-> assert_equal("dead", job_status(job))})
   let bufnr = bufnr('test_buffer')
-  call assert_equal(['hello'], getbufline(bufnr, 1, '$'))
+  call WaitForAssert({-> assert_equal(['hello'], getbufline(bufnr, 1, '$'))})
   call assert_equal('nofile', getbufvar(bufnr, '&buftype'))
   call assert_equal('hide', getbufvar(bufnr, '&bufhidden'))
+
   bdel test_buffer
   call assert_equal([], getbufline(bufnr, 1, '$'))
 
   let job = job_start('echo hello', {'out_io': 'buffer', 'out_name': 'test_buffer', 'out_msg': 0})
-  call WaitForAssert({-> assert_equal("dead", job_status(job))})
-  call assert_equal(['hello'], getbufline(bufnr, 1, '$'))
+  call WaitForAssert({-> assert_equal(['hello'], getbufline(bufnr, 1, '$'))})
   call assert_equal('nofile', getbufvar(bufnr, '&buftype'))
   call assert_equal('hide', getbufvar(bufnr, '&bufhidden'))
 

src/version.c

@@ -799,6 +799,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    693,
 /**/
     692,
 /**/