move tree-sitter packages out of flake

pkgs/development/tools/parsing/tree-sitter/grammars/tree-sitter-rasi/package.nix

@@ -0,0 +1,12 @@
+{ pkgs, fetchFromGitHub }:
+
+pkgs.tree-sitter.buildGrammar {
+  language = "rasi";
+  version = "0.1.2";
+  src = fetchFromGitHub {
+    owner = "Fymyte";
+    repo = "tree-sitter-rasi";
+    rev = "6c9bbcfdf5f0f553d9ebc01750a3aa247a37b8aa";
+    sha256 = "sha256-sPrIVgGGaBaXeqHNxjcdJ/S2FvxyV6rD9UPKU/tpspw=";
+  };
+}