Relax overly strict grpc-tools version requirement

[dcermak]

"~> 1.41.1" limits us to 1.41 which is already a year old now, relaxing this to "~> 1.41" allows us to pick up fresher and maintained releases.

@phinze you introduced this strict pin in a5f0064a86222ba55f0e162e16581ce1af8aaa69, any specific reason for going with this release?