vim-patch:9.1.0236: filetype: texlua files are not recognized

Problem:  filetype: texlua files are not recognized
Solution: Add '*.tlu' pattern for texlua files (Wu, Zhenyu)

Reference: https://github.com/TeX-Live/texdoc/tree/master/script

closes: vim/vim#14357

a75f4791b1

Co-authored-by: Wu, Zhenyu <wuzhenyu@ustc.edu>

runtime/lua/vim/filetype.lua

@@ -637,6 +637,7 @@ local extension = {
   nse = 'lua',
   rockspec = 'lua',
   lua = 'lua',
+  tlu = 'lua',
   luau = 'luau',
   lrc = 'lyrics',
   m = detect.m,