Bug/journaling sents out notifications even if there are no changes

[ulferts]

Ticket

https://community.openproject.org/wp/69448

What are you trying to accomplish?

Sits on top of #21332 to address certain unwanted behaviour identified:

• Even without a change in the journalized object
  • The journal gets its timestamp updated
  • A notification (OpenProject::Events::JOURNAL_CREATED) is sent out. Since saving of unchanged models in AR normally is an operation without side effects, journaling should behave the same. The code calls save repeatedly in a number of services and it should be ok to do so. This is also the reason for why multiple notifications are sent out on a PIR.
• The data and associated data of a journal is always deleted and then recreated. As of now, this didn't cause issues but it is just unnecessary.

Merge checklist

• [x] Added/updated tests