minor #7238 use Composer 2.8 to install dependencies (xabbuh)

This PR was merged into the 4.x branch.

Discussion
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use Composer 2.8 to install dependencies

Commits
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291cc59 use Composer 2.8 to install dependencies

Author: javiereguiluz

.github/workflows/ci.yaml

@@ -91,6 +91,7 @@ jobs:
                   coverage: none
                   extensions: mbstring, intl, pdo, pdo_sqlite, sqlite3
                   ini-values: date.timezone=UTC
+                  tools: composer:2.8
 
             - name: symfony/flex is required to install the correct symfony version
               if: ${{ matrix.symfony_version }}