MAGETWO-33947: Story stabilization

 - Fixed PAT test assertion

Author: guz-anton

dev/tests/performance/benchmark.jmx

@@ -624,7 +624,7 @@
           <RegexExtractor guiclass="RegexExtractorGui" testclass="RegexExtractor" testname="Regular Expression Extractor: Extarct product attribute id" enabled="true">
             <stringProp name="RegexExtractor.useHeaders">false</stringProp>
             <stringProp name="RegexExtractor.refname">configurable_attribute_id</stringProp>
-            <stringProp name="RegexExtractor.regex">&quot;spConfig&quot;:\{&quot;attributes&quot;:\{&quot;(\d+)&quot;</stringProp>
+            <stringProp name="RegexExtractor.regex">&quot;spConfig&quot;:[\s]*\{&quot;attributes&quot;:\{&quot;(\d+)&quot;</stringProp>
             <stringProp name="RegexExtractor.template">$1$</stringProp>
             <stringProp name="RegexExtractor.default"></stringProp>
             <stringProp name="RegexExtractor.match_number">1</stringProp>