Changed the regex delimiter for "The url should match"

Using / as a regex delimiter when matching an url is a pain because it
forces to escape all / in the url (and there more often / than " in
an URL).

i18n/de.xliff

@@ -99,7 +99,7 @@
             <target><![CDATA[/^(?:|ich )sollte auf "(?P<page>[^"]+)" sein$/]]></target>
         </trans-unit>
         <trans-unit id="the-url-should-match">
-            <source><![CDATA[/^the url should match "(?P<pattern>(?:[^"]|\\")*)"$/]]></source>
+            <source><![CDATA[/^the (?i)url(?-i) should match "(?P<pattern>(?:[^"]|\\")*)"$/]]></source>
             <target><![CDATA[/^die Webadresse sollte mit "(?P<pattern>(?:[^"]|\\")*)" übereinstimmen$/]]></target>
         </trans-unit>
         <trans-unit id="the-element-should-contain">