api-reference: fix hack/common.sh to determine root of repository
api-reference: fix hack/common.sh to determine root of repository

Fixes: #680

rmohr/kubevirt,stu-gott/kubevirt,davidvossel/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt,davidvossel/kubevirt,davidvossel/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt,rmohr/kubevirt,stu-gott/kubevirt,davidvossel/kubevirt,fabiand/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt,fabiand/kubevirt