minor #13687 [WebProfilerBundle] fix html lint on empty onclick (jrobeson)

This PR was merged into the 2.3 branch.

Discussion
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[WebProfilerBundle] fix html lint on empty onclick

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

The request collector has an empty onclick="" attribute
when {{ link }} isn't available. This tends to happen when
rendering the debug toolbar.

Commits
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a3a2f15 [WebProfilerBundle] fix html linting on empty onclick

src/Symfony/Bundle/WebProfilerBundle/Resources/views/Collector/request.html.twig

@@ -5,7 +5,7 @@
         {% if collector.controller.class is defined %}
             {% set link = collector.controller.file|file_link(collector.controller.line) %}
             <span class="sf-toolbar-info-class sf-toolbar-info-with-next-pointer">{{ collector.controller.class|abbr_class }}</span>
-            <span class="sf-toolbar-info-method" onclick="{% if link %}window.location='{{link|e('js')}}';window.event.stopPropagation();return false;{% endif %}">
+            <span class="sf-toolbar-info-method"{% if link %} onclick="window.location='{{link|e('js')}}';window.event.stopPropagation();return false;"{% endif %}>
                 {{ collector.controller.method }}
             </span>
         {% else %}