feat: add support for fsharp (#2021)

Co-authored-by: grenaad <g@g.com>
Co-authored-by: grenaad <dan4rie@gmail.com>

ftdetect/fsautocomplete.lua

@@ -0,0 +1,3 @@
+vim.cmd [[
+  au BufNewFile,BufRead *.fs,*.fsx,*.fsi set filetype=fsharp
+]]

lua/lvim/config/supported_languages.lua

@@ -26,6 +26,7 @@ return {
   "fennel",
   "fish",
   "fortran",
+  "fsharp",
   "gdscript",
   "glimmer",
   "go",