patch 8.2.3604: not all sudoers files are recognized

Problem:    Not all sudoers files are recognized.
Solution:   Add a file pattern. (Doug Kearns, closes #1192)

src/testdir/test_filetype.vim

@@ -482,7 +482,7 @@ let s:filename_checks = {
     \ 'st': ['file.st'],
     \ 'stata': ['file.ado', 'file.do', 'file.imata', 'file.mata'],
     \ 'stp': ['file.stp'],
-    \ 'sudoers': ['any/etc/sudoers', 'sudoers.tmp', '/etc/sudoers'],
+    \ 'sudoers': ['any/etc/sudoers', 'sudoers.tmp', '/etc/sudoers', 'any/etc/sudoers.d/file'],
     \ 'svg': ['file.svg'],
     \ 'svn': ['svn-commitfile.tmp', 'svn-commit-file.tmp', 'svn-commit.tmp'],
     \ 'swift': ['file.swift'],

src/version.c

@@ -757,6 +757,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3604,
 /**/
     3603,
 /**/