[FIX] http_routing: add missing space in qweb template

Since last refactoring of qweb to replace postprocessing cleaning by
onEval cleaning, the space between xml node are now ignored.

It's not a bug, but a tradeoff of the new implementation to avoid empty
line with code like
```xml
    <t t-if="condition">
        <div>...</div>
    </t>
```

closes odoo/odoo#94170

X-original-commit: 18ae4d804064dab284dadf53eed0681b8c56a555
Signed-off-by: Jérémy Kersten <jke@odoo.com>

addons/http_routing/views/http_routing_template.xml

@@ -43,7 +43,7 @@
                             <pre t-esc="exception"/>
                         </p>
                         <p>
-                            The error occurred while rendering the template <code t-esc="qweb_exception.name"/>
+                            The error occurred while rendering the template <code t-esc="qweb_exception.name"/> 
                             <t t-if="qweb_exception.html">and evaluating the following expression: <code t-esc="qweb_exception.html"/></t>
                         </p>
                     </div>