[Code format] Apply agreed Java format to Java files & include format check in pipeline

🎯 Purpose

This task has 2 goals which are not dissociable :

• Apply the agreed Java format to all Java files in the project using Spotless maven plugin
• Check the Java format of all Java files in the GitLab pipeline (this is already applied since the pipeline references 'henixdevelopment/open-source/opentestfactory/ci-common/java-ci')

ℹ️ This task will modify many files across the project. We will change the author of the commit to Java Format (dev_squash@henix.fr).
ℹ️ In order to keep this author information, the commits will not be squashed.

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This action is part of the effort to apply a common format for Java files across all our projects.