misc: test python 3.8 in CI, add cfg arg to RiscemuRunner

.github/workflows/ci-pytest.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.10']
+        python-version: ['3.8','3.10']
 
     steps:
     - uses: actions/checkout@v3

riscemu/riscemu_main.py

@@ -26,11 +26,11 @@ class RiscemuMain:
     input_files: List[str]
     selected_ins_sets: List[Type[InstructionSet]]
 
-    def __init__(self):
+    def __init__(self, cfg: Optional[RunConfig] = None):
         self.available_ins_sets = dict()
         self.selected_ins_sets = []
         self.available_file_loaders = []
-        self.cfg: Optional[RunConfig] = None
+        self.cfg: Optional[RunConfig] = cfg
         self.cpu: Optional[CPU] = None
         self.input_files = []
         self.selected_ins_sets = []