Update server policy name for iCaspr test

The policy "client_test_icaspr" was removed in cl/201053559

Updating the client tests with the new name.

Bug: 855730
Change-Id: I337ff743b9205f26649377b30fb15464bfbaabc8
Reviewed-on: https://chromium-review.googlesource.com/1112582Reviewed-by: Ryan Sturm <ryansturm@chromium.org>
Commit-Queue: Richard Bustamante <bustamante@google.com>
Cr-Commit-Position: refs/heads/master@{#569773}

tools/chrome_proxy/webdriver/lite_page.py

@@ -397,7 +397,7 @@ class LitePage(IntegrationTest):
       test_driver.AddChromeArg('--force-effective-connection-type=2G')
       # Set exp=client_test_icaspr to force iCASPR response.
       test_driver.AddChromeArg(
-          '--data-reduction-proxy-experiment=client_test_icaspr')
+          '--data-reduction-proxy-experiment=ihdp_integration')
 
       test_driver.LoadURL('http://check.googlezip.net/previews/ihdp.html')