feature #24080 Deprecated the web_profiler.position option (javiereguiluz)

This PR was squashed before being merged into the 3.4 branch (closes #24080).

Discussion
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Deprecated the web_profiler.position option

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no <!-- don't forget updating src/**/CHANGELOG.md files -->
| BC breaks?    | no
| Deprecations? | yes
| Tests pass?   | yes
| Fixed tickets | #23528
| License       | MIT
| Doc PR        | -

Related to #23728, which removes the feature for Symfony 4.0.

Commits
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53387b4335 Deprecated the web_profiler.position option

Author: fabpot

CHANGELOG.md

@@ -53,6 +53,8 @@ CHANGELOG
    `EventDispatcherDebugCommand`, `RouterDebugCommand`, `RouterMatchCommand`,
    `TranslationDebugCommand`, `TranslationUpdateCommand`, `XliffLintCommand`
     and `YamlLintCommand` classes have been marked as final
+ * Deprecated the `web_profiler.position` config option (in Symfony 4.0 the toolbar
+   will always be displayed at the bottom).
 
 3.3.0
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