Update translate model service browsertest model file path to something in the translate dir

Following https://chromium-review.googlesource.com/c/chromium/src/+/2628748,
this is the only code path that uses this file and I want to delete it.
Plus, the browser test currently doesn't depend on the file contents so
it can be any arbitrary file.

Change-Id: I65dcf1665f8b35a35247b6e80f2be68fa1c1b761
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2629657
Commit-Queue: Sophie Chang <sophiechang@chromium.org>
Commit-Queue: Scott Little <sclittle@chromium.org>
Reviewed-by: Michael Crouse <mcrouse@chromium.org>
Reviewed-by: Scott Little <sclittle@chromium.org>
Auto-Submit: Sophie Chang <sophiechang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843786}

chrome/browser/translate/translate_model_service_browsertest.cc

@@ -133,8 +133,9 @@ class TranslateModelServiceBrowserTest
 base::FilePath model_file_path() {
   base::FilePath model_file_path;
   EXPECT_TRUE(base::PathService::Get(base::DIR_SOURCE_ROOT, &model_file_path));
+  // TODO(crbug/1151400): Update this to a path that leads to an actual model.
   return model_file_path.AppendASCII(
-      "chrome/test/data/optimization_guide/unsignedmodel.crx3");
+      "chrome/test/data/translate/english_page.html");
 }
 
 IN_PROC_BROWSER_TEST_F(TranslateModelServiceBrowserTest,