feature #1451 Enable backtraces in Doctrine profiler (GromNaN)

This PR was merged into the main branch.

Discussion
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Enable backtraces in Doctrine profiler

I didn't know about this feature. It's very useful to find the origin of a specific query from the doctrine profiler panel.

I think it's a good idea to activate it on symfony/demo, as it allows you to demonstrate this functionality.

<img width="971" alt="image" src="https://github.com/symfony/demo/assets/400034/6aec0f4f-cbf2-4b99-9837-96a9a53c9666">

Commits
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97fa789 Enable backtraces in Doctrine profiler

config/packages/doctrine.yaml

@@ -43,3 +43,8 @@ when@prod:
                     adapter: cache.app
                 doctrine.system_cache_pool:
                     adapter: cache.system
+
+when@dev:
+    doctrine:
+        dbal:
+            profiling_collect_backtrace: true