Upgrade MyST and jupyter-myst-build-proxy (#72)

Author: mfisher87

docker/environment.yml

@@ -43,9 +43,9 @@ dependencies:
   - "maplibre"
 
   # Publishing
-  - "mystmd >=1.6.6"
+  - "mystmd >=1.7.0"
   - "typst"
-  - "jupyter-myst-build-proxy >=0.5.1"
+  - "jupyter-myst-build-proxy >=0.6.0"
 
   # Testing and validation
   - "ruff"