Use ipynb 0.2.

cabal.project

@@ -3,8 +3,8 @@ tests: True
 flags: +embed_data_files
 constraints: aeson >= 2.0.1.0
 
-source-repository-package
-  type: git
-  location: https://github.com/jgm/ipynb.git
-  tag: 00246af10885c2ad4413ace4f69a7e6c88297a08
+-- source-repository-package
+--   type: git
+--   location: https://github.com/jgm/ipynb.git
+--   tag: 00246af10885c2ad4413ace4f69a7e6c88297a08
 

stack.yaml

@@ -37,8 +37,7 @@ extra-deps:
 - commonmark-extensions-0.2.2.1
 - commonmark-pandoc-0.2.1.1
 - citeproc-0.6.0.1
-- git: https://github.com/jgm/ipynb.git
-  commit: 00246af10885c2ad4413ace4f69a7e6c88297a08
+- ipynb-0.2
 ghc-options:
    "$locals": -fhide-source-paths -Wno-missing-home-modules
 resolver: lts-18.10