minor #12487 Added a detail for getCrawler return. (TheGarious)

This PR was merged into the 4.3 branch.

Discussion
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Added a detail for getCrawler return.

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Commits
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a73f117 Added a detail for getCrawler return.

Author: javiereguiluz

testing.rst

@@ -535,6 +535,7 @@ You can also get the objects related to the latest request::
     // the BrowserKit response instance
     $response = $client->getInternalResponse();
 
+    // the Crawler instance
     $crawler = $client->getCrawler();
 
 Accessing the Container