Fix format warnings visible in BulkApiVarLength tests
Fix format warnings visible in BulkApiVarLength tests

Fixing:  warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘std::size_t {aka unsigned int}’ [-Wformat=]

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