Fixed a html error "Element ul is not closed" in logger.html.twig
minor #11085 Fixed a html error "Element ul is not closed" in logger.html.twig (hason)

This PR was merged into the 2.3 branch.

Discussion
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Fixed a html error "Element ul is not closed" in logger.html.twig

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

Commits
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e3bf86f Fixed a html error "Element ul is not closed" in logger.html.twig