Add more complete test ignores

[SpencerC]

Per #64, adds a slightly more complete example of how these rules might be used in the wild, including violations that require allow_comment_ignores: true to properly ignore.

I suggest adding code like this to the example and adding some language on https://buf.build/docs/build-systems/bazel along the lines of:

Important: allow_comment_ignores: true requires the bazel flag --experimental_proto_descriptor_sets_include_source_info in order to work. (for example bazel test //:root_proto_lint --experimental_proto_descriptor_sets_include_source_info)

Happy to do a PR for the doc update as well if someone can point me in the direction of that repo, if it exists (I couldn't find it easily myself).

[CLAassistant]

All committers have signed the CLA.

[srikrsna-buf]

The purpose of the example was to demonstrate lint failure. This repo only houses rules for using buf inside bazel but the behavior of buf is the same as it would be if used outside bazel. For an overview of linting and all the available options and rules please see this section of the docs.