ReportNode i18n

[flo-dup]

Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Does this PR already have an issue describing the problem?
No

What kind of change does this PR introduce?
Feature

What is the current behavior?
Language can hardly be changed

What is the new behavior (if this is a feature change)?
Language can be set by setting Locale to root ReportNode.

Does this PR introduce a breaking change or deprecate an API?

• Yes
• No

If yes, please check if the following requirements are fulfilled

• The Breaking Change or Deprecated label has been added
• The migration steps are described in the following section

What changes might users need to make in their application due to this PR? (migration steps)
All the message templates should be moved to a ResourceBundle.
Translation into french is expected - please request for help if needed.
withLocaleMessageTemplate(key, bundleBaseName) should be used instead of deprecated withMessageTemplate(key, messageTemplate)

[sonarqubecloud]

Quality Gate failed

Failed conditions
71.7% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube Cloud

[flo-dup]

It seems more natural to use java.text.MessageFormat now that we use ResourcesBundle, as it is the usual way to encode variable references inside. This would be quite a breaking change but it seems needed.
https://docs.oracle.com/javase/tutorial/i18n/format/messageFormat.html

[olperr1]

To help for this PR, some scripts are already in development in powsybl/powsybl-dev-tools#121