Git branch detection might block cache folder cleanup

Issue Summary

According to logs Bamboo was not able to remove repository cache folder and after reporting process for remove branch list was finished. It might be coincidence but it looks like git process for branch detection prevented Bamboo from cache folder removal

Steps to Reproduce

It's hard to reproduce and happened several times at customer environment. 

Expected Results

Executed by Bamboo processes are synchronized by folder and don't conflict

Actual Results

Cache folder kept in broken state

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available