fix(e2e): improve login command & remove useless clearCookies

The login command now returns a Cypress chain; this means that everything after
it will be executed after it's done; this will prevent race conditions

Cookies are cleaned between every run.

apps/datahub-e2e/src/e2e/datasets.cy.ts

@@ -2,7 +2,6 @@ import 'cypress-real-events'
 
 describe('datasets', () => {
   beforeEach(() => {
-    cy.clearCookies()
     cy.visit('/search')
 
     // aliases

tools/e2e/commands.ts

@@ -42,9 +42,11 @@ Cypress.Commands.add(
         headers: {
           'Content-Type': 'application/x-www-form-urlencoded',
         },
+        followRedirect: false,
       })
     })
-    if (redirect) cy.visit('/')
+    if (redirect) return cy.visit('/')
+    else return cy.window()
   }
 )
 
@@ -75,7 +77,8 @@ Cypress.Commands.add('clearFavorites', () => {
       .as('favoritesId')
   })
 
-  cy.getCookie('XSRF-TOKEN')
+  return cy
+    .getCookie('XSRF-TOKEN')
     .its('value')
     .then(function (token) {
       const favoritesId = this.favoritesId || []