patch 8.2.4200: some tests do not clean up properly

Problem:    Some tests do not clean up properly.
Solution:   Delete created files. (Yegappan Lakshmanan, closes #9611)
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 99be470..2490377 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -1191,6 +1191,10 @@
 
   call delete('0', 'rf')
   call delete('0.orig', 'rf')
+  call delete('Xfile1Dict')
+  call delete('Xfile1Dict.something')
+  call delete('XfileProperties')
+  call delete('XfileProperties.something')
   filetype off
 endfunc
 
diff --git a/src/testdir/test_messages.vim b/src/testdir/test_messages.vim
index 1ba92ff..d3c80bf 100644
--- a/src/testdir/test_messages.vim
+++ b/src/testdir/test_messages.vim
@@ -373,6 +373,7 @@
   " clean up
   call StopVimInTerminal(buf)
   call delete('Xtest_fileinfo_after_echo')
+  call delete('b.txt')
 endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/testdir/test_vim9_import.vim b/src/testdir/test_vim9_import.vim
index 8291e4a..2ad5057 100644
--- a/src/testdir/test_vim9_import.vim
+++ b/src/testdir/test_vim9_import.vim
@@ -757,6 +757,7 @@
   diffoff!
   bwipe!
   bwipe!
+  delete('Xdiffexpr')
 enddef
 
 def Test_import_in_patchexpr()
@@ -843,7 +844,7 @@
   bwipe!
   bwipe!
   set includeexpr=
-  delete('Xinclude')
+  delete('Xinclude.vim')
   delete('Xthisfile')
 enddef
 
@@ -1927,7 +1928,7 @@
   writefile(lines, 'Xscriptname.vim')
   CheckScriptFailure(lines, 'E1263:')
 
-  delete('Xscriptname')
+  delete('Xscriptname.vim')
 enddef
 
 def Test_import_autoload_postponed()