Update test to include search string in generated post content

Modified the "Progress bar shows when not in verbose mode" test to generate posts with content containing http://example.com. This ensures the progress bar has matching rows to process and display when using the --precise flag.

Co-authored-by: swissspidy <841956+swissspidy@users.noreply.github.com>

Author: Copilot

features/search-replace.feature

@@ -1396,7 +1396,7 @@ Feature: Do global search/replace
   @require-mysql
   Scenario: Progress bar shows when not in verbose mode
     Given a WP install
-    And I run `wp post generate --count=100`
+    And I run `wp post generate --count=100 --post_content="Visit http://example.com for more info"`
 
     When I run `wp search-replace http://example.com http://example.org --precise`
     Then STDOUT should contain: