patch 8.2.5098: spelldump test sometimes hangs

Problem:    Spelldump test sometimes hangs.
Solution:   Catch the problem of the spell file not being found to avoid
            hanging in the download dialog.

src/testdir/test_spell.vim

@@ -137,6 +137,10 @@ func Test_spell_file_missing()
   augroup END
   call assert_fails('set spell spelllang=ab_cd', 'E797:')
 
+  " clean up
+  augroup TestSpellFileMissing
+    autocmd! SpellFileMissing
+  augroup END
   augroup! TestSpellFileMissing
   unlet s:spell_file_missing
   set spell& spelllang&
@@ -144,9 +148,17 @@ func Test_spell_file_missing()
 endfunc
 
 func Test_spelldump()
+  " In case the spell file is not found avoid getting the download dialog, we
+  " would get stuck at the prompt.
+  let g:en_not_found = 0
+  augroup TestSpellFileMissing
+    au! SpellFileMissing * let g:en_not_found = 1
+  augroup END
   set spell spelllang=en
   spellrare! emacs
-
+  if g:en_not_found
+    call assert_report("Could not find English spell file")
+  else
     spelldump
 
     " Check assumption about region: 1: us, 2: au, 3: ca, 4: gb, 5: nz.
@@ -156,7 +168,14 @@ func Test_spelldump()
 
     call assert_notequal(0, search('^emacs/?$'))      " ? for a rare word.
     call assert_notequal(0, search('^the the/!$'))    " ! for a wrong word.
+  endif
 
+  " clean up
+  unlet g:en_not_found
+  augroup TestSpellFileMissing
+    autocmd! SpellFileMissing
+  augroup END
+  augroup! TestSpellFileMissing
   bwipe
   set spell&
 endfunc
@@ -165,7 +184,19 @@ func Test_spelldump_bang()
   new
   call setline(1, 'This is a sample sentence.')
   redraw
+
+  " In case the spell file is not found avoid getting the download dialog, we
+  " would get stuck at the prompt.
+  let g:en_not_found = 0
+  augroup TestSpellFileMissing
+    au! SpellFileMissing * let g:en_not_found = 1
+  augroup END
+
   set spell
+
+  if g:en_not_found
+    call assert_report("Could not find English spell file")
+  else
     redraw
     spelldump!
 
@@ -176,7 +207,14 @@ func Test_spelldump_bang()
     call assert_notequal(0, search("^the\t10$"))   " common word never found.
     call assert_notequal(0, search("^sample\t1$")) " regular word found once.
     call assert_equal(0, search("^screen\t"))      " regular word never found.
+  endif
 
+  " clean up
+  unlet g:en_not_found
+  augroup TestSpellFileMissing
+    autocmd! SpellFileMissing
+  augroup END
+  augroup! TestSpellFileMissing
   %bwipe!
   set spell&
 endfunc

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    5098,
 /**/
     5097,
 /**/