[PyROOT] Only inject TemplateProxy if not there already
[PyROOT] Only inject TemplateProxy if not there already

When several templated overloads exist, we only only need to inject
the corresponding TemplateProxy once.

olifre/root,olifre/root,olifre/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,karies/root,karies/root,olifre/root,olifre/root,karies/root,olifre/root,root-mirror/root,karies/root,olifre/root,root-mirror/root,root-mirror/root,karies/root,root-mirror/root,karies/root,karies/root,olifre/root,karies/root,olifre/root,root-mirror/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,karies/root,root-mirror/root