patch 8.0.0604: gF test fails still on MS-Windows

Problem:    gF test fails still on MS-Windows.
Solution:   Use : before the line number and remove it from 'isfname'.

src/testdir/test_gf.vim

@@ -38,7 +38,8 @@ func Test_gF()
   w! Xfile
   close
   new
-  call setline(1, ['one', 'Xfile@3', 'three'])
+  set isfname-=:
+  call setline(1, ['one', 'Xfile:3', 'three'])
   2
   call assert_fails('normal gF', 'E37:')
   call assert_equal(2, getcurpos()[1])
@@ -47,6 +48,7 @@ func Test_gF()
   call assert_equal('Xfile', bufname('%'))
   call assert_equal(3, getcurpos()[1])
 
+  set isfname&
   call delete('Xfile')
   call delete('Xfile2')
   bwipe Xfile

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    604,
 /**/
     603,
 /**/