minor #108 add jobs for Symfony 5.2 and PHP 8 (xabbuh)

This PR was merged into the 0.1-dev branch.

Discussion
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add jobs for Symfony 5.2 and PHP 8

Commits
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4dcc0b0 add jobs for Symfony 5.2 and PHP 8

Author: xabbuh

.github/workflows/ci.yaml

@@ -105,6 +105,10 @@ jobs:
           - php-version: '7.4'
             composer-options: '--prefer-stable'
             symfony-version: '5.1.*'
+          - php-version: '7.4'
+            composer-options: '--prefer-stable'
+            symfony-version: '5.2.*'
+          - php-version: '8.0'
 
     steps:
       - name: 'Check out'