[CI] Use stable version of psalm

Author: Nyholm

.github/workflows/psalm.yml

@@ -43,7 +43,7 @@ jobs:
           ([ -d "$COMPOSER_HOME" ] || mkdir "$COMPOSER_HOME") && cp .github/composer-config.json "$COMPOSER_HOME/config.json"
           export COMPOSER_ROOT_VERSION=$(grep ' VERSION = ' src/Symfony/Component/HttpKernel/Kernel.php | grep -P -o '[0-9]+\.[0-9]+').x-dev
           composer remove --dev --no-update --no-interaction symfony/phpunit-bridge
-          composer require --no-progress --ansi --no-plugins psalm/phar phpunit/phpunit:^9.5 php-http/discovery psr/event-dispatcher mongodb/mongodb jetbrains/phpstorm-stubs
+          composer require --no-progress --ansi --no-plugins psalm/phar:@stable phpunit/phpunit:^9.5 php-http/discovery psr/event-dispatcher mongodb/mongodb jetbrains/phpstorm-stubs
 
       - name: Generate Psalm baseline
         run: |