patch 9.0.1590: filetype test has trailing white space

Problem:    Filetype test has trailing white space.
Solution:   Remove trailing white space.

src/testdir/test_filetype.vim

@@ -768,7 +768,7 @@ def s:GetFilenameChecks(): dict<list<string>>
           '.zcompdump', '.zlogin', '.zlogout', '.zshenv', '.zshrc',
           '.zcompdump-file', '.zlog', '.zlog-file', '.zsh', '.zsh-file',
           'any/etc/zprofile', 'zlog', 'zlog-file', 'zsh', 'zsh-file'],
-    
+
     help: [$VIMRUNTIME .. '/doc/help.txt'],
     }
 enddef

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1590,
 /**/
     1589,
 /**/