Bump marked and jstransformer packages

Makes sense to bump these as part of this work, since they're being used under the hood to transform our files.

jstransformer-nunjucks Changelog: https://github.com/jstransformers/jstransformer-nunjucks/blob/master/CHANGELOG.md

- The major version bump simply adds the option to use custom Nunjucks loaders

jstransformer-marked Changelog: https://github.com/jstransformers/jstransformer-marked/blob/master/HISTORY.md

package.json

@@ -58,9 +58,9 @@
     "jest": "^27.2.3",
     "jest-puppeteer": "^4.1.1",
     "js-beautify": "^1.9.1",
-    "jstransformer-marked": "^1.0.3",
-    "jstransformer-nunjucks": "^0.5.0",
-    "marked": "^4.0.10",
+    "jstransformer-marked": "^1.2.0",
+    "jstransformer-nunjucks": "^1.0.0",
+    "marked": "^4.0.18",
     "metalsmith": "^2.5.0",
     "metalsmith-assets": "^0.1.0",
     "metalsmith-broken-link-checker": "^1.0.1",