Augment the tests for `Issue#related_branches`
Augment the tests for `Issue#related_branches`

- Test the case where we have a referenced merge request that's being
- excluded as a "related branch"
- This took a while to figure out, especially the
  `create_cross_references!` line.

LUMC/gitlabhq,dwrensha/gitlabhq,LUMC/gitlabhq,allysonbarros/gitlabhq,stoplightio/gitlabhq,dreampet/gitlab,allysonbarros/gitlabhq,htve/GitlabForChinese,Soullivaneuh/gitlabhq,martijnvermaat/gitlabhq,openwide-java/gitlabhq,allysonbarros/gitlabhq,stoplightio/gitlabhq,stoplightio/gitlabhq,iiet/iiet-git,dreampet/gitlab,dreampet/gitlab,jirutka/gitlabhq,daiyu/gitlab-zh,SVArago/gitlabhq,larryli/gitlabhq,darkrasid/gitlabhq,darkrasid/gitlabhq,openwide-java/gitlabhq,icedwater/gitlabhq,larryli/gitlabhq,axilleas/gitlabhq,iiet/iiet-git,shinexiao/gitlabhq,martijnvermaat/gitlabhq,mr-dxdy/gitlabhq,darkrasid/gitlabhq,daiyu/gitlab-zh,shinexiao/gitlabhq,dplarson/gitlabhq,dplarson/gitlabhq,SVArago/gitlabhq,openwide-java/gitlabhq,screenpages/gitlabhq,mr-dxdy/gitlabhq,mr-dxdy/gitlabhq,martijnvermaat/gitlabhq,screenpages/gitlabhq,LUMC/gitlabhq,htve/GitlabForChinese,icedwater/gitlabhq,daiyu/gitlab-zh,SVArago/gitlabhq,LUMC/gitlabhq,htve/GitlabForChinese,dplarson/gitlabhq,darkrasid/gitlabhq,jirutka/gitlabhq,axilleas/gitlabhq,mmkassem/gitlabhq,dreampet/gitlab,mmkassem/gitlabhq,daiyu/gitlab-zh,axilleas/gitlabhq,SVArago/gitlabhq,iiet/iiet-git,jirutka/gitlabhq,mmkassem/gitlabhq,screenpages/gitlabhq,Soullivaneuh/gitlabhq,t-zuehlsdorff/gitlabhq,htve/GitlabForChinese,t-zuehlsdorff/gitlabhq,martijnvermaat/gitlabhq,mmkassem/gitlabhq,openwide-java/gitlabhq,t-zuehlsdorff/gitlabhq,Soullivaneuh/gitlabhq,dplarson/gitlabhq,dwrensha/gitlabhq,screenpages/gitlabhq,icedwater/gitlabhq,dwrensha/gitlabhq,shinexiao/gitlabhq,t-zuehlsdorff/gitlabhq,axilleas/gitlabhq,allysonbarros/gitlabhq,dwrensha/gitlabhq,jirutka/gitlabhq,icedwater/gitlabhq,larryli/gitlabhq,larryli/gitlabhq,stoplightio/gitlabhq,mr-dxdy/gitlabhq,shinexiao/gitlabhq,iiet/iiet-git,Soullivaneuh/gitlabhq