ci: adding testing for Python 3.13 (#259)

Author: Borda

.github/workflows/ci-test.yml

@@ -20,7 +20,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
         os: ["ubuntu-latest", "macOS-latest", "windows-latest"]
         backend: ["local", "db"]
         exclude: