patch 8.2.0444: swap file test fails on some systems

Problem:    Swap file test fails on some systems.
Solution:   Preserve the swap file. Send NL terminated keys.
diff --git a/src/testdir/test_swap.vim b/src/testdir/test_swap.vim
index cc452c3..612832c 100644
--- a/src/testdir/test_swap.vim
+++ b/src/testdir/test_swap.vim
@@ -1,5 +1,6 @@
 " Tests for the swap feature
 
+source check.vim
 source shared.vim
 source term_util.vim
 
@@ -352,11 +353,12 @@
 
 " Test for selecting 'q' in the attention prompt
 func Test_swap_prompt_splitwin()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run vim in terminal'
-  endif
+  CheckRunVimInTerminal
+
   call writefile(['foo bar'], 'Xfile1')
   edit Xfile1
+  preserve  " should help to make sure the swap file exists
+
   let buf = RunVimInTerminal('', {'rows': 20})
   call term_sendkeys(buf, ":set nomore\n")
   call term_sendkeys(buf, ":set noruler\n")
@@ -365,9 +367,9 @@
   call WaitForAssert({-> assert_match('^\[O\]pen Read-Only, (E)dit anyway, (R)ecover, (Q)uit, (A)bort: $', term_getline(buf, 20))})
   call term_sendkeys(buf, "q")
   call term_wait(buf)
-  call term_sendkeys(buf, ":")
+  call term_sendkeys(buf, ":\<CR>")
   call WaitForAssert({-> assert_match('^:$', term_getline(buf, 20))})
-  call term_sendkeys(buf, "echomsg winnr('$')\<CR>")
+  call term_sendkeys(buf, ":echomsg winnr('$')\<CR>")
   call term_wait(buf)
   call WaitForAssert({-> assert_match('^1$', term_getline(buf, 20))})
   call StopVimInTerminal(buf)
diff --git a/src/version.c b/src/version.c
index 2e219a9..4230f54 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    444,
+/**/
     443,
 /**/
     442,