vim-patch:9.2.0562: filetype: SGF files are not recognized

Problem:  filetype: SGF files are not recognized
Solution: Detect *.sgf as sgf filetype
          (Borys Lykah)

Reference:
https://www.red-bean.com/sgf/index.html

closes: vim/vim#20349

dda45ba88f

Co-authored-by: Borys Lykah <lykahb@fastmail.com>

runtime/lua/vim/filetype.lua

@@ -1191,6 +1191,7 @@ local extension = {
   sdl = 'sdl',
   sed = 'sed',
   sexp = 'sexplib',
+  sgf = 'sgf',
   bash = detect.bash,
   bats = detect.bash,
   cygport = detect.bash,

test/old/testdir/test_filetype.vim

@@ -740,6 +740,7 @@ func s:GetFilenameChecks() abort
     \ 'services': ['/etc/services', 'any/etc/services'],
     \ 'setserial': ['/etc/serial.conf', 'any/etc/serial.conf'],
     \ 'sexplib': ['file.sexp'],
+    \ 'sgf': ['file.sgf'],
     \ 'sh': ['.bashrc', '.bash_profile', '.bash-profile', '.bash_logout', '.bash-logout', '.bash_aliases', '.bash-aliases', '.bash_history', '.bash-history',
     \        '/tmp/bash-fc-3Ozjlw', '/tmp/bash-fc.3Ozjlw', 'PKGBUILD', 'file.bash', '/usr/share/doc/bash-completion/filter.sh',
     \        '/etc/udev/cdsymlinks.conf', 'any/etc/udev/cdsymlinks.conf', 'file.bats', '.ash_history', 'any/etc/neofetch/config.conf', '.xprofile',