Use not found constant in more places

Use STATUS_NOT_FOUND in code quality report actions
and related component specs and store specs

app/assets/javascripts/reports/codequality_report/store/actions.js

 import pollUntilComplete from '~/lib/utils/poll_until_complete';
+import { STATUS_NOT_FOUND } from '../../constants';
 import * as types from './mutation_types';
 import { parseCodeclimateMetrics } from './utils/codequality_parser';
 
@@ -9,7 +10,7 @@ export const fetchReports = ({ state, dispatch, commit }) => {
 
   return pollUntilComplete(state.reportsPath)
     .then(({ data }) => {
-      if (data.status === 'not_found') {
+      if (data.status === STATUS_NOT_FOUND) {
         return dispatch('receiveReportsError', data);
       }
       return dispatch('receiveReportsSuccess', {

spec/frontend/reports/codequality_report/grouped_codequality_reports_app_spec.js

@@ -3,6 +3,7 @@ import Vuex from 'vuex';
 import CodequalityIssueBody from '~/reports/codequality_report/components/codequality_issue_body.vue';
 import GroupedCodequalityReportsApp from '~/reports/codequality_report/grouped_codequality_reports_app.vue';
 import { getStoreConfig } from '~/reports/codequality_report/store';
+import { STATUS_NOT_FOUND } from '~/reports/constants';
 import { parsedReportIssues } from './mock_data';
 
 const localVue = createLocalVue();
@@ -140,7 +141,7 @@ describe('Grouped code quality reports app', () => {
 
     describe('when base report was not found', () => {
       beforeEach(() => {
-        mockStore.state.status = 'not_found';
+        mockStore.state.status = STATUS_NOT_FOUND;
       });
 
       it('renders a help icon with more information', () => {

spec/frontend/reports/codequality_report/store/actions_spec.js

@@ -5,6 +5,7 @@ import axios from '~/lib/utils/axios_utils';
 import createStore from '~/reports/codequality_report/store';
 import * as actions from '~/reports/codequality_report/store/actions';
 import * as types from '~/reports/codequality_report/store/mutation_types';
+import { STATUS_NOT_FOUND } from '~/reports/constants';
 import { reportIssues, parsedReportIssues } from '../mock_data';
 
 const pollInterval = 123;
@@ -91,7 +92,7 @@ describe('Codequality Reports actions', () => {
 
     describe('when base report is not found', () => {
       it('commits REQUEST_REPORTS and dispatches receiveReportsError', (done) => {
-        const data = { status: 'not_found' };
+        const data = { status: STATUS_NOT_FOUND };
         mock.onGet(`${TEST_HOST}/codequality_reports.json`).reply(200, data);
 
         testAction(

spec/frontend/reports/codequality_report/store/getters_spec.js

 import createStore from '~/reports/codequality_report/store';
 import * as getters from '~/reports/codequality_report/store/getters';
-import { LOADING, ERROR, SUCCESS } from '~/reports/constants';
+import { LOADING, ERROR, SUCCESS, STATUS_NOT_FOUND } from '~/reports/constants';
 
 describe('Codequality reports store getters', () => {
   let localState;
@@ -78,7 +78,7 @@ describe('Codequality reports store getters', () => {
   describe('codequalityPopover', () => {
     describe('when base report is not available', () => {
       it('returns a popover with a documentation link', () => {
-        localState.status = 'not_found';
+        localState.status = STATUS_NOT_FOUND;
         localState.helpPath = 'codequality_help.html';
 
         expect(getters.codequalityPopover(localState).title).toEqual(

spec/frontend/reports/codequality_report/store/mutations_spec.js

 import createStore from '~/reports/codequality_report/store';
 import mutations from '~/reports/codequality_report/store/mutations';
+import { STATUS_NOT_FOUND } from '~/reports/constants';
 
 describe('Codequality Reports mutations', () => {
   let localState;
@@ -82,7 +83,7 @@ describe('Codequality Reports mutations', () => {
     });
 
     it('sets status based on error object', () => {
-      const error = { status: 'not_found' };
+      const error = { status: STATUS_NOT_FOUND };
       mutations.RECEIVE_REPORTS_ERROR(localState, error);
 
       expect(localState.status).toEqual(error.status);