Remove unused apollo configuration

- origninally added to use apollo in a Vuex-context
- ended up going a different direction, so removing now

ee/app/assets/javascripts/security_dashboard/graphql/provider.js

 import Vue from 'vue';
 import VueApollo from 'vue-apollo';
 import { IntrospectionFragmentMatcher } from 'apollo-cache-inmemory';
-import createDefaultClient, { fetchPolicies } from '~/lib/graphql';
+import createDefaultClient from '~/lib/graphql';
 import introspectionQueryResultData from './fragmentTypes.json';
 
 Vue.use(VueApollo);
@@ -21,13 +21,6 @@ const defaultClient = createDefaultClient(
   },
 );
 
-export const vuexApolloClient = createDefaultClient(
-  {},
-  {
-    fetchPolicy: fetchPolicies.NO_CACHE,
-  },
-);
-
 export default new VueApollo({
   defaultClient,
 });