2.4.0-RC2 release

[anchitj]

No description provided.

[emasab]

Thanks Anchit, please add this to CHANGELOG

# 2.4.0

## Enhancements

- References librdkafka.redist 2.4.0. Refer to the [librdkafka v2.4.0 release notes](https://github.com/confluentinc/librdkafka/releases/tag/v2.4.0) for more information.

And change these lines

Install-Package Confluent.Kafka -Version 2.3.0
dotnet add package -v 2.3.0 Confluent.Kafka

[anchitj]

Thanks Anchit, please add this to CHANGELOG

# 2.4.0

## Enhancements

- References librdkafka.redist 2.4.0. Refer to the [librdkafka v2.4.0 release notes](https://github.com/confluentinc/librdkafka/releases/tag/v2.4.0) for more information.

And change these lines

Install-Package Confluent.Kafka -Version 2.3.0
dotnet add package -v 2.3.0 Confluent.Kafka

I think we should only change the README lines once doing the final release. So that if anyone is following directly the mater README they won't use the RC version.

[emasab]

@anchitj we can keep the CHANGELOG in sync with the code we merge, that is a work in progress too until we release.
They will know it's a RC if they start testing it. Maybe you can change it to
# 2.4.0 (in progress).

About the Install-Package and dotnet add package ok, let's change them with final release