patch 8.2.4790: lilypond filetype not recognized

Problem:    Lilypond filetype not recognized.
Solution:   Add patterns for lilypond. (Doug Kearns)
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 390bc9c..f0d46a4 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -306,6 +306,7 @@
     \ 'libao': ['/etc/libao.conf', '/.libao', 'any/.libao', 'any/etc/libao.conf'],
     \ 'lifelines': ['file.ll'],
     \ 'lilo': ['lilo.conf', 'lilo.conf-file'],
+    \ 'lilypond': ['file.ly', 'file.ily'],
     \ 'limits': ['/etc/limits', '/etc/anylimits.conf', '/etc/anylimits.d/file.conf', '/etc/limits.conf', '/etc/limits.d/file.conf', '/etc/some-limits.conf', '/etc/some-limits.d/file.conf', 'any/etc/limits', 'any/etc/limits.conf', 'any/etc/limits.d/file.conf', 'any/etc/some-limits.conf', 'any/etc/some-limits.d/file.conf'],
     \ 'liquid': ['file.liquid'],
     \ 'lisp': ['file.lsp', 'file.lisp', 'file.asd', 'file.el', 'file.cl', '.emacs', '.sawfishrc', 'sbclrc', '.sbclrc'],
diff --git a/src/version.c b/src/version.c
index b837fcb..9a76fdf 100644
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4790,
+/**/
     4789,
 /**/
     4788,