[ReleasePR synapse] Add storageRedundancy property to Synapse v3 database GET and PUT (#1736)

Create to sync Azure/azure-rest-api-specs#13425
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Author: msftbot[bot]

schemas/2020-04-01-preview/Microsoft.Synapse.json

@@ -169,6 +169,23 @@
             }
           ],
           "description": "The max size of the database expressed in bytes."
+        },
+        "storageRedundancy": {
+          "oneOf": [
+            {
+              "type": "string",
+              "enum": [
+                "Geo",
+                "GeoZone",
+                "Local",
+                "Zone"
+              ]
+            },
+            {
+              "$ref": "https://schema.management.azure.com/schemas/common/definitions.json#/definitions/expression"
+            }
+          ],
+          "description": "Storage redundancy of the database."
         }
       },
       "description": "The sql database's properties."