fix: add missing types for interface methods

Author: johanneskoester

snakemake_interface_executor_plugins/jobs.py

@@ -101,18 +101,18 @@ def benchmark(self) -> Optional[str]: ...
 
     @property
     @abstractmethod
-    def message(self): ...
+    def message(self) -> Optional[str]: ...
 
 
 class GroupJobExecutorInterface(ABC):
     @property
     @abstractmethod
-    def jobs(self): ...
+    def jobs(self) -> Iterable[SingleJobExecutorInterface]: ...
 
     @property
     @abstractmethod
-    def groupid(self): ...
+    def groupid(self) -> str: ...
 
     @property
     @abstractmethod
-    def toposorted(self): ...
+    def toposorted(self) -> Sequence[Sequence[SingleJobExecutorInterface]]: ...