ci: add testing against Python 3.12

Author: ylobankov

.github/workflows/test.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11']
+        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11', '3.12']
         tarantool-version: ['2.8', '2.10']
 
     steps: