Update python version list for CI testing

Newer versions of poetry only support Python 3.9+.

Author: reosarevok

.github/workflows/test.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python_version: [ '3.8', '3.9', '3.10', '3.11', '3.12' ]
+        python_version: [ '3.9', '3.10', '3.11', '3.12', '3.13' ]
     steps:
     - uses: actions/checkout@v2
     - name: Install Python