Fix rating on ChartJS extension page

HTTP Status 500 - Invalid URL [https://extensions.xwiki.org/xwiki/bin/view/XWiki/Ratings?xpage=plain&outputSyntax=plain&doc=extensions:Extension.Chart\.js Integration.WebHome&vote=5]type Exception reportmessage Invalid URL [https://extensions.xwiki.org/xwiki/bin/view/XWiki/Ratings?xpage=plain&outputSyntax=plain&doc=extensions:Extension.Chart\.js Integration.WebHome&vote=5]description The server encountered an internal error that prevented it from fulfilling this request.exceptionjavax.servlet.ServletException: Invalid URL [https://extensions.xwiki.org/xwiki/bin/view/XWiki/Ratings?xpage=plain&outputSyntax=plain&doc=extensions:Extension.Chart\.js Integration.WebHome&vote=5]
	org.xwiki.resource.servlet.RoutingFilter.constructExtendedURL(RoutingFilter.java:192)
	org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:99)
root causeorg.xwiki.resource.CreateResourceReferenceException: Invalid URL [https://extensions.xwiki.org/xwiki/bin/view/XWiki/Ratings?xpage=plain&outputSyntax=plain&doc=extensions:Extension.Chart\.js Integration.WebHome&vote=5]
	org.xwiki.url.ExtendedURL.<init>(ExtendedURL.java:122)
	org.xwiki.resource.servlet.RoutingFilter.constructExtendedURL(RoutingFilter.java:190)
	org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:99)
root causejava.net.URISyntaxException: Illegal character in query at index 119: https://extensions.xwiki.org/xwiki/bin/view/XWiki/Ratings?xpage=plain&outputSyntax=plain&doc=extensions:Extension.Chart\.js Integration.WebHome&vote=5
	java.net.URI$Parser.fail(URI.java:2848)
	java.net.URI$Parser.checkChars(URI.java:3021)
	java.net.URI$Parser.parseHierarchical(URI.java:3111)
	java.net.URI$Parser.parse(URI.java:3053)
	java.net.URI.<init>(URI.java:588)
	java.net.URL.toURI(URL.java:946)
	org.xwiki.url.ExtendedURL.<init>(ExtendedURL.java:120)
	org.xwiki.resource.servlet.RoutingFilter.constructExtendedURL(RoutingFilter.java:190)
	org.xwiki.resource.servlet.RoutingFilter.doFilter(RoutingFilter.java:99)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.57 logs.Apache Tomcat/7.0.57