Julia v1.9 (#340)

Author: dlfivefifty

.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
         version:
           - '1.6'
           - '1'
-          - 'nightly'
+          - '^1.9.0-0'
         os:
           - ubuntu-latest
           - macOS-latest