vim-patch:9.2.0217: filetype: cto files are not recognized (#38400)

Problem:  filetype: cto files are not recognized
Solution: Detect *.cto as concerto filetype (Jamie Shorten)

Add filetype detection for the Concerto Modelling Language. Concerto
is a schema language by the Accord Project for defining data models
used in smart legal contracts and business networks.

Reference:
Language spec: https://concerto.accordproject.org
Tree-sitter grammar: https://github.com/accordproject/concerto-tree-sitter

closes: vim/vim#19760

68f9dedba4

Co-authored-by: Jamie Shorten <jamie@jamieshorten.com>

runtime/lua/vim/filetype.lua

@@ -330,6 +330,7 @@ local extension = {
   cbl = 'cobol',
   atg = 'coco',
   recipe = 'conaryrecipe',
+  cto = 'concerto',
   ctags = 'conf',
   hook = function(_path, bufnr)
     return M._getline(bufnr, 1) == '[Trigger]' and 'confini' or nil