Resolve "Consistent error handling in frontend"

Closes #148 (closed)

frontend/src/components/submission_notes/SubmissionCorrection.vue

@@ -135,6 +135,10 @@ export default {
         SubmissionNotes.SET_ORIG_FEEDBACK(feedback)
         this.$emit('feedbackCreated')
       }).catch(err => {
+        // ignore trivial errors as those are handled
+        // by an interceptor
+        if (err.message.includes("Request failed")) return
+
         this.$notify({
           title: 'Feedback creation Error!',
           text: err.message,