fix: clear module from sys.modules before importing service

Signed-off-by: Frost Ming <[email protected]>

Author: frostming

src/bentoml/_internal/service/loader.py

@@ -84,6 +84,8 @@ def import_service(
     if model_store is not global_model_store:
         BentoMLContainer.model_store.set(model_store)
 
+    svc: AnyService | Service | None = None
+
     def _restore(restore_model_store: bool = False) -> None:
         """Undo changes to sys.path, cwd and model store"""
         if restore_model_store and model_store is not global_model_store:
@@ -92,6 +94,8 @@ def _restore(restore_model_store: bool = False) -> None:
             sys.path.remove(working_dir)
         if prev_cwd is not None:
             os.chdir(prev_cwd)
+        if svc is not None and (import_string := getattr(svc, "_import_str", None)):
+            sys.modules.pop(import_string.split(":", 1)[0], None)
 
     try:
         svc = _do_import(svc_import_path, working_dir, reload)