Fixed getCSV to use data from global store

frontend/src/views/ViewObservations.vue

@@ -257,12 +257,12 @@ export default {
     getCSV: function() {
       Vue.axios
         .post("/observations/csv", {
-          site: this.siteSelection,
-          tutor: this.tutorSelection,
+          site: this.$store.state.search.site,
+          tutor: this.$store.state.search.tutor,
           startDate: moment(this.startDate).format("YYYY-MM-DD"),
           endDate: moment(this.endDate).format("YYYY-MM-DD"),
-          whom: this.whom,
-          person: this.person
+          whom: this.$store.state.search.whom,
+          person: this.$store.state.search.person
         })
         .then(response => {
           let blob = new Blob([response.data], { type: "text/csv" });