fix: add markdownlint target

It was missing from the website package.json, even though
it was checking the website directory. So should be there.

The markdownlint-cli2 tool does **not** check in the parent
directory, unlike the other tools, so add explicit config.

Signed-off-by: Anders F Björklund <anders.f.bjorklund@gmail.com>

website/package.json

@@ -15,6 +15,8 @@
     "typecheck": "tsc",
     "format:check": "prettier --check '**/*.{md,js}' 'src/**/*.{css,ts,tsx}'",
     "format:fix": "prettier --write '**/*.{md,js}' 'src/**/*.{css,ts,tsx}'",
+    "markdownlint:check": "markdownlint-cli2 --config ../.markdownlint.yaml \"**/*.md\" \"#node_modules\"",
+    "markdownlint:fix": "markdownlint-cli2-fix --config ../.markdownlint.yaml \"**/*.md\" \"#node_modules\"",
     "lint:check": "cd .. && eslint website --ext js,ts,tsx",
     "lint:fix": "cd .. && eslint website --fix --ext js,ts,tsx"
   },