fix: use getBackendBaseUrl instead of hardcoded string

packages/website/ts/components/modals/modal_contact.tsx

@@ -12,6 +12,7 @@ import { Icon } from 'ts/components/icon';
 import { Input, InputWidth } from 'ts/components/modals/input';
 import { Heading, Paragraph } from 'ts/components/text';
 import { GlobalStyle } from 'ts/constants/globalStyle';
+import { utils } from 'ts/utils/utils';
 
 export enum ModalContactType {
     General = 'GENERAL',
@@ -279,7 +280,7 @@ export class ModalContact extends React.Component<Props> {
         try {
             // Disabling no-unbound method b/c no reason for _.isEmpty to be bound
             // tslint:disable:no-unbound-method
-            const response = await fetch(`https://website-api.0xproject.com${endpoint}`, {
+            const response = await fetch(`${utils.getBackendBaseUrl()}${endpoint}`, {
                 method: 'post',
                 mode: 'cors',
                 credentials: 'same-origin',

packages/website/ts/components/newsletter_form.tsx

@@ -4,6 +4,7 @@ import styled, { withTheme } from 'styled-components';
 import { ThemeValuesInterface } from 'ts/components/siteWrap';
 import { colors } from 'ts/style/colors';
 import { errorReporter } from 'ts/utils/error_reporter';
+import { utils } from 'ts/utils/utils';
 
 interface FormProps {
     theme: ThemeValuesInterface;
@@ -92,7 +93,7 @@ class Form extends React.Component<FormProps> {
         }
 
         try {
-            await fetch('https://website-api.0x.org/newsletter_subscriber/substack', {
+            await fetch(`${utils.getBackendBaseUrl()}/newsletter_subscriber/substack`, {
                 method: 'post',
                 mode: 'cors',
                 headers: {