bump protobufjs to "^6.11.3"

[ocofaigh]

The package protobufjs before 6.11.3 are vulnerable to Prototype Pollution which can allow an attacker to add/modify properties of the Object.prototype.

This vulnerability can occur in multiple ways:

1. by providing untrusted user input to util.setProperty or to ReflectionObject.setParsedOption functions
2. by parsing/loading .proto files
   Publish Date: 2022-05-27

URL: CVE-2022-25878

[murgatroid99]

This change has been published in @grpc/proto-loader version 0.6.13.