Update dependency arch/python-markdown-it-py to v4.2.0

Author: renovate[bot]

pyproject.toml

@@ -22,7 +22,7 @@ dependencies = [
     "pydantic==2.13.4",
     "cryptography==49.0.0",
     "textual==8.2.8",
-    "markdown-it-py==4.0.0",
+    "markdown-it-py==4.2.0",
     "linkify-it-py==2.1.0",
 ]