#425: fixed type errors found by mypy

exasol_integration_test_docker_environment/lib/test_environment/abstract_spawn_test_environment.py

@@ -118,7 +118,7 @@ def collect_shell_variables(self, test_environment_info) -> ShellVariables:
         )
 
     def _start_database(self, attempt) \
-            -> Generator[BaseTask, BaseTask, Tuple[DockerNetworkInfo, DatabaseInfo, bool, Optional[ContainerInfo]]]:
+            -> Generator[BaseTask, None, Tuple[DockerNetworkInfo, DatabaseInfo, bool, Optional[ContainerInfo]]]:
         network_info = yield from self._create_network(attempt)
         ssl_volume_info = None
         if self.create_certificates:
@@ -127,7 +127,7 @@ def _start_database(self, attempt) \
         is_database_ready = yield from self._wait_for_database(database_info, attempt) # type: ignore
         return network_info, database_info, is_database_ready, test_container_info # type: ignore
 
-    def _create_ssl_certificates(self) -> Generator:
+    def _create_ssl_certificates(self) -> Generator[BaseTask, None, Optional[DockerVolumeInfo]]:
         ssl_info_future = yield from self.run_dependencies(self.create_ssl_certificates())
         ssl_info = self.get_values_from_future(ssl_info_future)
         return ssl_info # type: ignore

exasol_integration_test_docker_environment/lib/test_environment/create_certificates/create_ssl_certificates_task.py

@@ -56,7 +56,7 @@ def run_task(self):
 
         self.return_object(self.volume_info)
 
-    def build_image(self) -> Generator["BaseTask", PickleTarget, Set[str]]:
+    def build_image(self) -> Generator[BaseTask, None, Set[str]]:
         task = self.create_child_task(task_class=DockerCertificateContainerBuild,
                                       certificate_container_root_directory=self._temp_resource_directory.tmp_directory)
         image_infos_future = yield from self.run_dependencies(task)