contributing: Tweak title of PR testing section
contributing: Tweak title of PR testing section

manthey/girder,opadron/girder,girder/girder,Xarthisius/girder,manthey/girder,msmolens/girder,essamjoubori/girder,RafaelPalomar/girder,RafaelPalomar/girder,RafaelPalomar/girder,sutartmelson/girder,data-exp-lab/girder,girder/girder,adsorensen/girder,adsorensen/girder,sutartmelson/girder,manthey/girder,Xarthisius/girder,salamb/girder,opadron/girder,essamjoubori/girder,sutartmelson/girder,opadron/girder,Kitware/girder,adsorensen/girder,msmolens/girder,essamjoubori/girder,adsorensen/girder,jbeezley/girder,kotfic/girder,girder/girder,jbeezley/girder,sutartmelson/girder,kotfic/girder,Xarthisius/girder,data-exp-lab/girder,kotfic/girder,Xarthisius/girder,jbeezley/girder,kotfic/girder,adsorensen/girder,RafaelPalomar/girder,manthey/girder,salamb/girder,essamjoubori/girder,Xarthisius/girder,salamb/girder,kotfic/girder,salamb/girder,essamjoubori/girder,data-exp-lab/girder,Kitware/girder,opadron/girder,girder/girder,msmolens/girder,sutartmelson/girder,msmolens/girder,msmolens/girder,RafaelPalomar/girder,Kitware/girder,opadron/girder,Kitware/girder,salamb/girder,data-exp-lab/girder,data-exp-lab/girder,jbeezley/girder