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]

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