minor symfony#31067 Optimize SVGs (MartijnCuppens)

This PR was merged into the 3.4 branch.

Discussion
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Optimize SVGs

| Q             | A
| ------------- | ---
| Branch?       | 3.4 <!-- see below -->
| Bug fix?      | yes
| New feature?  | no <!-- don't forget to update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | no <!-- don't forget to update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | /   <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | / <!-- required for new features -->

Used [svgo](https://github.com/svg/svgo) to optimize the svgs. I kept the `viewBox` attribute to keep the aspects when SVGs are rescaled.

I also added `insert_final_newline = false` to the `.editorconfig` file because the newlines are removed from the SVGs and there's only one line left.

Commits
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4614cea Optimize SVGs

Author: nicolas-grekas