minor #1207 Bump dependencies to Symfony 5.2.7 (rosier)

This PR was merged into the main branch.

Discussion
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Bump dependencies to Symfony 5.2.7

~~I also dumped shivammathur/setup-php to fix the CI macos-latest / PHP 7.3 build~~

~~https://github.com/symfony/demo/runs/2486726663?check_suite_focus=true#step:3:57~~

nvm, seems unrelated

Commits
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eb808c8 Dump dependencies to Symfony 5.2.7

Author: javiereguiluz