Add link to Mapping Data Flows

Poor click through analysis revealed we have a lot of traffic to mapping data flows in the Next Steps at the very bottom of the page, and a lot of clicks in-page to the Mapping Data Flow properties section much higher up on the page, which has no direct link to the Mapping Data Flows article though.  Hopefully adding this link should improve click-through.  My theory is most people are looking for Mapping Data Flows article but many may click to that section, not find it there, and end up navigating away with search, etc.
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cc: @jianleishen

Author: jonburchel

articles/data-factory/format-json.md

@@ -193,7 +193,7 @@ When copying data from JSON files, copy activity can automatically detect and pa
 
 ## Mapping data flow properties
 
-In mapping data flows, you can read and write to JSON format in the following data stores: [Azure Blob Storage](connector-azure-blob-storage.md#mapping-data-flow-properties), [Azure Data Lake Storage Gen1](connector-azure-data-lake-store.md#mapping-data-flow-properties), and [Azure Data Lake Storage Gen2](connector-azure-data-lake-storage.md#mapping-data-flow-properties).
+In [mapping data flows](concepts-data-flow-overview.md), you can read and write to JSON format in the following data stores: [Azure Blob Storage](connector-azure-blob-storage.md#mapping-data-flow-properties), [Azure Data Lake Storage Gen1](connector-azure-data-lake-store.md#mapping-data-flow-properties), and [Azure Data Lake Storage Gen2](connector-azure-data-lake-storage.md#mapping-data-flow-properties).
 
 ### Source properties