patch 9.0.0424: gitattributes files are not recognized

Problem:    gitattributes files are not recognized.
Solution:   Add patterns to match gitattributes files. (closes #11085)

Author: ObserverOfTime

runtime/filetype.vim

@@ -720,7 +720,11 @@ au BufNewFile,BufRead *.git/worktrees/*/config.worktree		setf gitconfig
 au BufNewFile,BufRead .gitmodules,*.git/modules/*/config	setf gitconfig
 if !empty($XDG_CONFIG_HOME)
   au BufNewFile,BufRead $XDG_CONFIG_HOME/git/config		setf gitconfig
+  au BufNewFile,BufRead $XDG_CONFIG_HOME/git/attributes		setf gitattributes
 endif
+au BufNewFile,BufRead .gitattributes,*.git/info/attributes	setf gitattributes
+au BufNewFile,BufRead */.config/git/attributes  		setf gitattributes
+au BufNewFile,BufRead */etc/gitattributes  			setf gitattributes
 au BufNewFile,BufRead git-rebase-todo		setf gitrebase
 au BufRead,BufNewFile .gitsendemail.msg.??????	setf gitsendemail
 au BufNewFile,BufRead *.git/*

src/testdir/test_filetype.vim

@@ -213,6 +213,7 @@ let s:filename_checks = {
     \ 'gedcom': ['file.ged', 'lltxxxxx.txt', '/tmp/lltmp', '/tmp/lltmp-file', 'any/tmp/lltmp', 'any/tmp/lltmp-file'],
     \ 'gemtext': ['file.gmi', 'file.gemini'],
     \ 'gift': ['file.gift'],
+    \ 'gitattributes': ['file.git/info/attributes', '.gitattributes', '/.config/git/attributes', '/etc/gitattributes', '/usr/local/etc/gitattributes', 'some.git/info/attributes'],
     \ 'gitcommit': ['COMMIT_EDITMSG', 'MERGE_MSG', 'TAG_EDITMSG', 'NOTES_EDITMSG', 'EDIT_DESCRIPTION'],
     \ 'gitconfig': ['file.git/config', 'file.git/config.worktree', 'file.git/worktrees/x/config.worktree', '.gitconfig', '.gitmodules', 'file.git/modules//config', '/.config/git/config', '/etc/gitconfig', '/usr/local/etc/gitconfig', '/etc/gitconfig.d/file', 'any/etc/gitconfig.d/file', '/.gitconfig.d/file', 'any/.config/git/config', 'any/.gitconfig.d/file', 'some.git/config', 'some.git/modules/any/config'],
     \ 'gitolite': ['gitolite.conf', '/gitolite-admin/conf/file', 'any/gitolite-admin/conf/file'],

src/version.c

@@ -703,6 +703,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    424,
 /**/
     423,
 /**/