Bamboo database version validation not working correctly allowing version rollbacks

Issue Summary

Database version validation not working correctly allowing version rollbacks without rolling back the database.

This is reproducible on Data Center: yes

Steps to Reproduce

1. Install Bamboo 8.0.9
2. Upgrade to Bamboo 9.3.5
3. Stop Bamboo 9.3.5
4. Edit $BAMBOO_HOME/bamboo.cfg.xml (don't change the shared home configuration)
5. Change buildNumber to 80012
6. Start Bamboo 8.0.9

Expected Results

Bamboo does not start as the database version is 90307 and reports an error about version mismatch.

Actual Results

Bamboo 8.0.9 starts on a 90307 database, changes the database and shared home version to 80012

Workaround

N/A