fix(dicom-json): Series metadata retrieve (#2726)

There was a typo in DicomJSON datasource to retrieve metadata. This was
causing an error in Mode.jsx (line 52)

extensions/default/src/DicomJSONDataSource/index.js

@@ -134,7 +134,7 @@ function createDicomJSONApi(dicomJsonConfig) {
     },
     retrieve: {
       series: {
-        metaData: ({
+        metadata: ({
           StudyInstanceUID,
           madeInClient = false,
           customSort,