Use responsive iframe control for charts (#49)

* Use responsive iframe control to charts

* Move external Grafana link to Dashboard page

* Remove unused embedded style class

* Add button label

src/components/useStyles.jsx

@@ -166,8 +166,12 @@ const useStyles = makeStyles((theme) => ({
   grow: {
     flexGrow: 1,
   },
-  iframe: {
+  embeddedWrapper: {
     marginTop: 10,
+    position: "relative",
+    overflow: "hidden",
+    width: "100%",
+    paddingTop: "56.25%",
   },
 }));