Add support for protobuf input format

[npawar]

Currently the supported input formats for batch ingestion are CSV, AVRO, JSON, Parquet, Thrift, ORC.

Add support for Protobuf.

[reallocf]

Hey @npawar - I'm interested in working on this one. Would be my first time contributing to the project, would love to help! 🎉

I'm guessing I'll create another pinot-input-format and mirror pinot-json or pinot-csv or pinot-parquet. Then update RecordReaderFactory in pinot-spi and probably the CreateSementCommand in pinot-tools. Where else should I be updating? I'm sure I'm missing a bunch of places :)

[kishoreg]

You pretty much got everything right. I think @KKcorps has already started working on this. Can you pick up the support for filtering during ingestion? #5268

[reallocf]

@kishoreg - thanks for letting me know! Definitely don't want to duplicate work 👍 will take a look at #5268

[KKcorps]

Taking this up!