bug symfony#46553 [WebProfilerBundle] normalizer and encoder can be undefined in template (kor3k)

This PR was merged into the 6.1 branch.

Discussion
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[WebProfilerBundle] normalizer and encoder can be undefined in template

| Q             | A
| ------------- | ---
| Branch?       | 6.1
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix symfony#46537 <!-- prefix each issue number with "Fix #", no need to create an issue if none exist, explain below instead -->
| License       | MIT
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Commits
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18990bf [WebProfilerBundle] normalizer and encoder can be undefined in template

Author: fabpot

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

@@ -188,7 +188,9 @@
 {% macro render_normalizer_cell(item, index, method) %}
     {% set nested_normalizers_id = 'nested-normalizers-' ~ method ~ '-' ~ index %}
 
+    {% if item.normalizer is defined %}
     <span class="nowrap"><a href="{{ item.normalizer.file|file_link(item.normalizer.line) }}" title="{{ item.normalizer.file }}">{{ item.normalizer.class }}</a> ({{ '%.2f'|format(item.normalizer.time * 1000) }} ms)</span>
+    {% endif %}
 
     {% if item.normalization|length > 1 %}
         <div>
@@ -207,7 +209,9 @@
 {% macro render_encoder_cell(item, index, method) %}
     {% set nested_encoders_id = 'nested-encoders-' ~ method ~ '-' ~ index %}
 
+    {% if item.encoder is defined %}
     <span class="nowrap"><a href="{{ item.encoder.file|file_link(item.encoder.line) }}" title="{{ item.encoder.file }}">{{ item.encoder.class }}</a> ({{ '%.2f'|format(item.encoder.time * 1000) }} ms)</span>
+    {% endif %}
 
     {% if item.encoding|length > 1 %}
         <div>