ignore/types: add MDX format to Markdown types

Ref https://mdxjs.com/

Closes BurntSushi#2142

Author: BurntSushi

CHANGELOG.md

@@ -10,7 +10,7 @@ Unreleased changes. Release notes have not yet been written.
 
 Feature enhancements:
 
-* Added or improved file type filtering for DITA, Elixir, Fuchsia, Gentoo, GraphQL, USD, V
+* Added or improved file type filtering for DITA, Elixir, Fuchsia, Gentoo, GraphQL, Markdown, USD, V
 * [FEATURE #2195](https://github.com/BurntSushi/ripgrep/issues/2195):
   When `extra-verbose` mode is enabled in zsh, show extra file type info.
 * [FEATURE #2409](https://github.com/BurntSushi/ripgrep/pull/2409):

crates/ignore/src/default_types.rs

@@ -160,9 +160,18 @@ pub const DEFAULT_TYPES: &[(&str, &[&str])] = &[
         "*.mdwn",
         "*.mkd",
         "*.mkdn",
+        "*.mdx",
     ]),
     ("matlab", &["*.m"]),
-    ("md", &["*.markdown", "*.md", "*.mdown", "*.mdwn", "*.mkd", "*.mkdn"]),
+    ("md", &[
+        "*.markdown",
+        "*.md",
+        "*.mdown",
+        "*.mdwn",
+        "*.mkd",
+        "*.mkdn",
+        "*.mdx",
+    ]),
     ("meson", &["meson.build", "meson_options.txt"]),
     ("minified", &["*.min.html", "*.min.css", "*.min.js"]),
     ("mint", &["*.mint"]),