Consider removing poperties values from workflow.xml which are already defined in default-config.xml

[marekhorst]

Some properties (e.g. *SparkExecutorOverhead) values apart from being declared in default-config.xml file (which is part of the environment, originally defined in this config git repo) are also explicitly declared in workflow.xml file.

We should consider removing properties values. One drawback: dev runs will need to have those properties explicitly declared which does not look like a big deal.