feat: Create modal to merge two contacts (#2457)

app/javascript/dashboard/api/accountActions.js

@@ -0,0 +1,18 @@
+/* global axios */
+
+import ApiClient from './ApiClient';
+
+class AccountActions extends ApiClient {
+  constructor() {
+    super('actions', { accountScoped: true });
+  }
+
+  merge(parentId, childId) {
+    return axios.post(`${this.url}/contact_merge`, {
+      base_contact_id: parentId,
+      mergee_contact_id: childId,
+    });
+  }
+}
+
+export default new AccountActions();

app/javascript/dashboard/api/specs/accountActions.spec.js

@@ -0,0 +1,23 @@
+import accountActionsAPI from '../accountActions';
+import ApiClient from '../ApiClient';
+import describeWithAPIMock from './apiSpecHelper';
+
+describe('#ContactsAPI', () => {
+  it('creates correct instance', () => {
+    expect(accountActionsAPI).toBeInstanceOf(ApiClient);
+    expect(accountActionsAPI).toHaveProperty('merge');
+  });
+
+  describeWithAPIMock('API calls', context => {
+    it('#merge', () => {
+      accountActionsAPI.merge(1, 2);
+      expect(context.axiosMock.post).toHaveBeenCalledWith(
+        '/api/v1/actions/contact_merge',
+        {
+          base_contact_id: 1,
+          mergee_contact_id: 2,
+        }
+      );
+    });
+  });
+});