switch descriptastorus to use rmg channel version

the rmg one is the correct amount of outdated for our use case

environment.yml

@@ -15,15 +15,14 @@
 # - May 15, 2023 Added this changelog, added inline documentation,
 #   made dependency list more explicit (@JacksonBurns).
 # - October 16, 2023 Switched RDKit to conda-forge and
-#   descripatastorus to katanagraph
+#   descripatastorus to explicitly RMG channel
 #
 name: rmg_env
 channels:
   - defaults
   - rmg
   - conda-forge
   - cantera
-  - katanagraph
 dependencies:
 # System-level dependencies - we could install these at the OS level
 # but by installing them in the conda environment we get better control
@@ -53,7 +52,7 @@ dependencies:
   # https://github.com/chemprop/chemprop/issues/428 for why
   # TL;DR: scipy introduced incompatible API changes with 2.6.1+ of
   # descriptastorus
-  - katanagraph::descriptastorus
+  - rmg::descriptastorus
 
 # general-purpose external software tools
   - conda-forge::julia>=1.8.5,!=1.9.0