Fix ty warnings in XML report tests

Author: Beeeeeeee-c

test/recommend/test_recommend_pipeline.py

@@ -9,7 +9,7 @@
 
 import javalang
 import javalang.tree
-from lxml import etree
+from lxml import etree  # type: ignore[import-untyped]
 
 from aibolit import __main__ as aibolit_main
 from aibolit.config import Config

test/scripts/test_calculate_metrics.py

@@ -12,8 +12,9 @@ def load_calculate_metrics_module():
         raise RuntimeError(f'Failed to load module spec from {script_path}')
     if spec.loader is None:
         raise RuntimeError(f'Failed to load module loader from {script_path}')
+    loader = spec.loader
     module = importlib.util.module_from_spec(spec)
-    spec.loader.exec_module(module)
+    loader.exec_module(module)
     return module