docs: Ignore mkdocs.yml and generated docs

mkdocs.yml contains some reference to Python package data
which fails the pre-commit check.

Docs HTML is generated in docs/site/

.gitignore

@@ -1,8 +1,9 @@
+.venvs
 .devenv*
 devenv.local.nix
 .direnv
 .pre-commit-config.yaml
 
 .benchmarks
 
-.venvs
+docs/site/

devenv.nix

@@ -64,7 +64,10 @@ in
     check-added-large-files.enable = true;
     check-json.enable = true;
     check-toml.enable = true;
-    check-yaml.enable = true;
+    check-yaml = {
+      enable = true;
+      excludes = [ "docs/mkdocs.yml" ];
+    };
     trim-trailing-whitespace = {
       enable = true;
       excludes = [ ".*.md$" ];