[security_page] improve force logout (elastic#170227)

## Summary

Addressing `forceLogout` flakiness
https://buildkite.com/elastic/appex-qa-serverless-kibana-ftr-tests/builds/370

```
Error: timed out waiting for Waiting for logout to complete
    at onFailure (retry_for_truthy.ts:39:13)
    at retryForSuccess (retry_for_success.ts:59:13)
    at retryForTruthy (retry_for_truthy.ts:27:3)
    at RetryService.waitFor (retry.ts:59:5)
    at SecurityPageObject.forceLogout (security_page.ts:319:7)
    at Object.forceLogout (svl_common_page.ts:95:7)
    at Context. (view_case.ts:44:7)
    at Object.apply (wrap_function.js:73:16)
```

<img width="1294" alt="image"
src="https://github.com/elastic/kibana/assets/10977896/92ff13da-2c80-4eb7-8b3e-63779fb61075">


Flaky-test-runner:
https://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/3839
200/200

x-pack/test/functional/page_objects/security_page.ts

@@ -41,6 +41,8 @@ export class SecurityPageObject extends FtrService {
   private readonly monacoEditor = this.ctx.getService('monacoEditor');
   private readonly es = this.ctx.getService('es');
 
+  delay = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms));
+
   public loginPage = Object.freeze({
     login: async (username?: string, password?: string, options: LoginOptions = {}) => {
       if (!(await this.isLoginFormVisible())) {
@@ -316,20 +318,27 @@ export class SecurityPageObject extends FtrService {
       await this.waitForLoginPage();
     } else {
       this.log.debug('Waiting for logout to complete');
-      await this.retry.waitFor('Waiting for logout to complete', async () => {
+      await this.retry.waitFor('logout to complete', async () => {
         // There are cases when browser/Kibana would like users to confirm that they want to navigate away from the
         // current page and lose the state (e.g. unsaved changes) via native alert dialog.
         const alert = await this.browser.getAlert();
         if (alert?.accept) {
           await alert.accept();
         }
 
+        await this.retry.waitFor('URL redirects to finish', async () => {
+          const urlBefore = await this.browser.getCurrentUrl();
+          await this.delay(1000);
+          const urlAfter = await this.browser.getCurrentUrl();
+          return urlAfter === urlBefore;
+        });
+
+        const currentUrl = await this.browser.getCurrentUrl();
         if (this.config.get('serverless')) {
           // Logout might trigger multiple redirects, but in the end we expect the Cloud login page
-          this.log.debug('Wait 5 sec for Cloud login page to be displayed');
-          return await this.find.existsByDisplayedByCssSelector('.login-form-password', 5000);
+          return currentUrl.includes('/login') || currentUrl.includes('/projects');
         } else {
-          return !(await this.browser.getCurrentUrl()).includes('/logout');
+          return !currentUrl.includes('/logout');
         }
       });
     }