docs: Remove additional_vim_regex_highlighting

This option is no longer needed unless [org_highlight_latex_and_related](https://github.com/nvim-orgmode/orgmode/blob/master/DOCS.md#org_highlight_latex_and_related) is enabled

Author: kristijanhusak

DOCS.md

@@ -266,6 +266,17 @@ Possible values:
   * between `\[` and `\]` delimiters - example: `\[ a=-\sqrt{2} \]`
   * between `\(` and `\)` delimiters - example: `\( b=2 \)`
 
+**This option requires setting `additional_vim_regex_highlighting = {'org'}` in tree-sitter configuration since its old Vim syntax**:
+```lua
+require('nvim-treesitter.configs').setup {
+  highlight = {
+    enable = true,
+    additional_vim_regex_highlighting = {'org'}, -- This line is needed
+  },
+  ensure_installed = {'org'},
+}
+```
+
 #### **org_startup_indented**
 
 *type*: `boolean`<br />

README.md

@@ -45,7 +45,6 @@ Use your favourite package manager:
     require('nvim-treesitter.configs').setup({
       highlight = {
         enable = true,
-        additional_vim_regex_highlighting = { 'org' },
       },
       ensure_installed = { 'org' },
     })
@@ -110,13 +109,8 @@ require('orgmode').setup_ts_grammar()
 
 -- Treesitter configuration
 require('nvim-treesitter.configs').setup {
-  -- If TS highlights are not enabled at all, or disabled via `disable` prop,
-  -- highlighting will fallback to default Vim syntax highlighting
   highlight = {
     enable = true,
-    -- Required for spellcheck, some LaTex highlights and
-    -- code block highlights that do not have ts grammar
-    additional_vim_regex_highlighting = {'org'},
   },
   ensure_installed = {'org'}, -- Or run :TSUpdate org
 }

scripts/minimal_init.lua

@@ -31,7 +31,6 @@ require('lazy').setup({
       require('nvim-treesitter.configs').setup({
         highlight = {
           enable = true,
-          additional_vim_regex_highlighting = { 'org' },
         },
         ensure_installed = { 'org' },
       })