patch 9.1.1206: tests: test_filetype fails when a file is a directory

Problem:  tests: test_filetype fails when a file is a directory
          (Eisuke Kawashima)
Solution: When encountering a directory instead of a file, skip that
          particular filetype test

fixes: #16894

Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_filetype.vim

@@ -938,6 +938,9 @@ def s:CheckItems(checks: dict<list<string>>)
 
   for [ft, names] in items(checks)
     for i in range(0, len(names) - 1)
+      if isdirectory(fnameescape(names[i]))
+        continue
+      endif
       new
       try
         exe 'edit ' .. fnameescape(names[i])

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1206,
 /**/
     1205,
 /**/