bug #19204 Fix typo in http_client.rst (Hmache)

This PR was submitted for the 6.4 branch but it was merged into the 5.4 branch instead.

Discussion
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Fix typo in http_client.rst

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Commits
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0cc5fb3 Fix typo in http_client.rst

Author: OskarStark

http_client.rst

@@ -1809,7 +1809,7 @@ assertions on the request before returning the mocked response::
         },
     ];
 
-    $client = new MockHttpClient($expectedRequest);
+    $client = new MockHttpClient($expectedRequests);
 
     // ...