Getting Started With WDL

When posting my WDL to dockstore i get the following message in the Description section of dock store
There is a syntax error, please check the WDL file.

The wdl file has been tested and it works fine, I wonder if its related to the script being written in the latest version of WDL which is 1.0. Is dockstore able to recognize the change in syntax for WDL 1.0?

Link to workflow : https://dockstore.org/workflows/github.com/gatk-workflows/gatk4-exome-analysis-pipeline/ExomeGermlineSingleSample:1.0.0?tab=info
Link to different versions of WDL : https://github.com/openwdl/wdl/tree/master/versions