We had a similar issue to this with Glossary Items being picked up in processes where an acronym spells out a word.      We worked around this by putting putting full stops or a marker to break the links  ,  i.e  WAS  we put W.A.S .      Thinking the same could apply to your test system tag maybe  edit it to say  TEST_SYSTEM   then this will break the linkages .   

Thanks ClaireT - this will work for new ones - unfortunately changing an existing system title just changes it in all processes it’s linked to as well. :(

I see that it has been put in previously as an idea to have something changed so a system can be deleted without having to go into all processes - if interested the idea for voting on is: IDEA-I-3674

@stapleer if you change the system name to xxtest (as an example, and remembering to remove any nickname tags associated in the system record) and then let the software update overnight you should be able to then go into the systems listing and delete the system without changing any terminology in the existing processes.

does that help at all?