update CI

Author: b-yogesh

.github/workflows/unittest.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.11", "3.12", "3.13" ]
+        python-version: ["3.12", "3.13" ]
 
     steps:
       - name: checkout xcube-clms