#2103 [BUG] Failed to run spark job when using flytekit remote Issue created by pingsutw ### Describe the bug I am able to run spark jobs when using flytectl to register the workflow and trigger them on the flyte console. However, I got the below error messages when using the flytekit remote client to execute the workflow. E0126 092112.800044 1 workers.go:102] error syncing 'flytesnacks-development/f4fbbb51f24e6436695b': failed at Node[n0]. RuntimeExecutionError: failed during plugin execution, caused by: failed to execute handle for plugin [spark]: [BadTaskSpecification] invalid TaskSpecification [fields{key"sparkConf" value{struct value{fields: {key:"spark.driver.cores" value{string value"1"}} fields{key"spark.driver.memory" value{string value"1000M"}} fields: {key:"spark.executor.cores" value{string value"1"}} fields{key"spark.executor.instances" value{string value"2"}} fields: {key:"spark.executor.memory" value{string value"1000M"}}}}}]., caused by: either MainApplicationFile or MainClass must be set ### Expected behavior Remote clients should be able to execute the spark workflow ### Additional context to reproduce from flytekit.remote import FlyteRemote import spark_dataframe.workflows.example remote = FlyteRemote( flyte_admin_url=localhost:30081, insecure=True, default_project="flytesnacks", default_domain="development", image_config=ImageConfig( default_image=Image(name="default", fqn="spark", tag="v1") ) ) remote.execute(spark_dataframe.workflows.example.my_smart_schema, inputs={}, version=version, wait=False) ### Screenshots ### Are you sure this issue hasn't been raised already? • Yes ### Have you read the Code of Conduct? • Yes flyteorg/flyte