patch 8.1.0925: terminal scrollback test still still flaky

Problem:    Terminal scrollback test still still flaky.
Solution:   Explicitly set the shell.  Disable ruler. (Ozaki Kiichi,
            closes #3966)

src/testdir/dumps/Test_terminal_01.dump

@@ -7,7 +7,7 @@
 |4|8| @72
 >4|9| @72
 |~+0#4040ff13&| @73
-|!+2#ffffff16#00e0003|/|b|i|n|/|t|c|s|h| |[|T|e|r|m|i|n|a|l|]| @35|5|1|,|1| @10|B|o|t
+|!+2#ffffff16#00e0003|/|b|i|n|/|s|h| |[|T|e|r|m|i|n|a|l|]| @55
 | +0#0000000#ffffff0@74
 |~+0#4040ff13&| @73
 |~| @73
@@ -16,5 +16,5 @@
 |~| @73
 |~| @73
 |~| @73
-|[+1#0000000&|N|o| |N|a|m|e|]| @47|0|,|0|-|1| @9|A|l@1
+|[+1#0000000&|N|o| |N|a|m|e|]| @65
 | +0&&@74

src/testdir/dumps/Test_terminal_02.dump

@@ -7,7 +7,7 @@
 >4|8| @72
 |4|9| @72
 |~+0#4040ff13&| @73
-|!+2#ffffff16#00e0003|/|b|i|n|/|t|c|s|h| |[|T|e|r|m|i|n|a|l|]| @35|5|0|,|1| @10|B|o|t
+|!+2#ffffff16#00e0003|/|b|i|n|/|s|h| |[|T|e|r|m|i|n|a|l|]| @55
 | +0#0000000#ffffff0@74
 |~+0#4040ff13&| @73
 |~| @73
@@ -16,5 +16,5 @@
 |~| @73
 |~| @73
 |~| @73
-|[+1#0000000&|N|o| |N|a|m|e|]| @47|0|,|0|-|1| @9|A|l@1
+|[+1#0000000&|N|o| |N|a|m|e|]| @65
 | +0&&@74

src/testdir/dumps/Test_terminal_03.dump

@@ -7,7 +7,7 @@
 |4|9| @72
 |o|n|e| |m|o|r|e| |l|i|n|e| @61
 > @74
-|!+2#ffffff16#00e0003|/|b|i|n|/|t|c|s|h| |[|r|u|n@1|i|n|g|]| @36|4|3|,|1| @10|B|o|t
+|!+2#ffffff16#00e0003|/|b|i|n|/|s|h| |[|r|u|n@1|i|n|g|]| @56
 | +0#0000000#ffffff0@74
 |~+0#4040ff13&| @73
 |~| @73
@@ -16,5 +16,5 @@
 |~| @73
 |~| @73
 |~| @73
-|[+1#0000000&|N|o| |N|a|m|e|]| @47|0|,|0|-|1| @9|A|l@1
+|[+1#0000000&|N|o| |N|a|m|e|]| @65
 | +0&&@74

src/testdir/test_terminal.vim

@@ -310,26 +310,24 @@ func Test_terminal_postponed_scrollback()
 
   call writefile(range(50), 'Xtext')
   call writefile([
+	\ 'set shell=/bin/sh noruler',
 	\ 'terminal',
-	\ 'sleep 400m',
-	\ 'call feedkeys("tail -n 100 -f Xtext\<CR>", "xt")',
 	\ 'sleep 200m',
+	\ 'call feedkeys("tail -n 100 -f Xtext\<CR>", "xt")',
+	\ 'sleep 100m',
 	\ 'call feedkeys("\<C-W>N", "xt")',
 	\ ], 'XTest_postponed')
   let buf = RunVimInTerminal('-S XTest_postponed', {})
   " Check that the Xtext lines are displayed and in Terminal-Normal mode
-  call term_wait(buf)
   call VerifyScreenDump(buf, 'Test_terminal_01', {})
 
   silent !echo 'one more line' >>Xtext
   " Sceen will not change, move cursor to get a different dump
   call term_sendkeys(buf, "k")
-  call term_wait(buf)
   call VerifyScreenDump(buf, 'Test_terminal_02', {})
 
   " Back to Terminal-Job mode, text will scroll and show the extra line.
   call term_sendkeys(buf, "a")
-  call term_wait(buf)
   call VerifyScreenDump(buf, 'Test_terminal_03', {})
 
   call term_wait(buf)

src/version.c

@@ -783,6 +783,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    925,
 /**/
     924,
 /**/