Merge pull request #663 from ccnmtl/dependabot/pip/markdown-3.9

Bump markdown from 3.8.2 to 3.9

Author: ndittren

test_reqs.txt

@@ -1,4 +1,4 @@
-Markdown==3.8.2  # pyup: <3.2
+Markdown==3.9  # pyup: <3.2
 coverage==7.10.6
 importlib_metadata<8.8
 typing_extensions==4.15.0