How to switch to 2.1.0 release tag / branch in Eclipse IDE

I am new to Eclipse IDE and the openHAB build process. So I followed the instructions to setup from scratch and everything works as expected but I run into a java runtime exception which is an already known issue and described here: [Automation] circular service reference #3635. Since my dashboard is not started and accessible, I wonder if I should simply switch to release 2.1.0 tag because the official release works like a charm.

So how can I switch the whole openHAB project within Eclipse IDE from master branches to the release 2.1.0 tag?