fix github actions

Author: fashxp

.github/ci/scripts/setup-pimcore-x-environment.sh

@@ -18,7 +18,7 @@ cp .github/ci/pimcore_x/files/.env ./
 # temp. until elasticsearch/elasticsearch 7.11 is released
 composer config minimum-stability "dev"
 composer config prefer-stable true
-composer require pimcore/pimcore:dev-master --no-update
+composer require pimcore/pimcore:10.x-dev --no-update
 
 # move that to composer.json when only pimcore X
 composer require codeception/module-symfony:^1.6.0 --no-update