vim-patch:8.2.4781: Maxima files are not recognized

Problem:    Maxima files are not recognized.
Solution:   Add patterns to detect Maxima files. (Doron Behar, closes vim/vim#10211)
d0a20c9d11

runtime/filetype.vim

@@ -154,6 +154,10 @@ au BufNewFile,BufRead *.asp
 " Grub (must be before catch *.lst)
 au BufNewFile,BufRead */boot/grub/menu.lst,*/boot/grub/grub.conf,*/etc/grub.conf setf grub
 
+" Maxima, see:
+" https://maxima.sourceforge.io/docs/manual/maxima_71.html#file_005ftype_005fmaxima
+au BufNewFile,BufRead *.mc,*.demo,*.dem,*.dm{1,2,3,t},*.wxm,maxima-init.mac setf maxima
+
 " Assembly (all kinds)
 " *.lst is not pure assembly, it has two extra columns (address, byte codes)
 au BufNewFile,BufRead *.asm,*.[sS],*.[aA],*.mac,*.lst	call dist#ft#FTasm()

src/nvim/testdir/test_filetype.vim

@@ -337,6 +337,8 @@ let s:filename_checks = {
     \ 'markdown': ['file.markdown', 'file.mdown', 'file.mkd', 'file.mkdn', 'file.mdwn', 'file.md'],
     \ 'mason': ['file.mason', 'file.mhtml', 'file.comp'],
     \ 'master': ['file.mas', 'file.master'],
+    \ 'maxima': ['file.mc', 'file.demo', 'file.dem', 'file.dmt', 'file.dm1', 'file.dm2', 'file.dm3',
+    \            'file.wxm', 'maxima-init.mac'],
     \ 'mel': ['file.mel'],
     \ 'meson': ['meson.build', 'meson_options.txt'],
     \ 'messages': ['/log/auth', '/log/cron', '/log/daemon', '/log/debug', '/log/kern', '/log/lpr', '/log/mail', '/log/messages', '/log/news/news', '/log/syslog', '/log/user',