New function: combine metadata and observations

Fetch datastream metadata together with the observations

public/js/appChart.js

@@ -393,6 +393,21 @@ export const getCombinedObservationsFromAllNextLinks = function (
     });
 };
 
+const getMetadataPlusObservationsForChart = async function (promiseArray) {
+  const combinedResolvedPromises = [];
+
+  for (const promise of promiseArray) {
+    try {
+      const resolvedPromise = await promise;
+
+      combinedResolvedPromises.push(resolvedPromise);
+    } catch (err) {
+      console.log(err);
+    }
+  }
+  return combinedResolvedPromises;
+};
+
 /**
  * Retrieve all the Observations from an array of Observations promises
  * @async