fix: escape hyphen to prevent markdown list rendering inside manual

langauge list

Author: thilobillerbeck

core/src/content/learning-manuals/02-nixpkgs-manual.mdx

@@ -29,7 +29,7 @@ The Nix Packages collection (Nixpkgs) is a set of thousands of packages for the
     [Haskell](/manual/nixpkgs/stable/#haskell) -
     [Elm](/manual/nixpkgs/stable/#sec-elm) - [BEAM Languages (Erlang, Elixir,
     LFE)](/manual/nixpkgs/stable/#sec-beam) - [Lua](/manual/nixpkgs/stable/#lua)
-    - [Idris](/manual/nixpkgs/stable/#idris) -
+    \- [Idris](/manual/nixpkgs/stable/#idris) -
     [Coq](/manual/nixpkgs/stable/#sec-language-coq) -
     [Perl](/manual/nixpkgs/stable/#sec-language-perl) -
     [OCaml](/manual/nixpkgs/stable/#sec-language-ocaml) -