Description of problem:
After migrating from 6.1 to 6.2, exception will pop up after navigating to Deploy->Rule Deployments

Version-Release number of selected component (if applicable):
6.2.x

How reproducible:
always

Steps to Reproduce:
1. Start BRMS 6.1.x and register Decision Server
2. Install BRMS 6.2.x and set org.uberfire.nio.git.dir so it points to BRMS 6.1.x git repository
3. Configure BRMS 6.2.x with kie-server and start it
4. log into the business-central and navigate to Deploy -> Rule Deployments
Following error is thrown:
https://gist.github.com/agiertli/c8cc605e0deaae55f289

Actual results:
Exception is thrown and kie-server is not displayed

Expected results:
Exception is not thrown and kie-server is displayed

Additional info:
This can be workarounded by removing entries from remote/* directory in origin/servers remote branch of system.git repository.