Added documentation on getting started with GCS

[mhmohona]

Added documentation on getting started with GCS with following content:

• Setting Up Google Cloud Storage
• Configuring Apache Iceberg to Use GCS
• Loading Data into Iceberg Tables
• Querying Data from Iceberg Tables

Refers to - apache/iceberg#7948

[nastra]

@mhmohona thanks for adding some docs on this topic. Typically docs like this should land under https://github.com/apache/iceberg/tree/master/docs. During the release process those are then copied over to the iceberg-docs repo

[mhmohona]

Hello @nastra, thank you for your guidance. I have created PR for GCS in main Iceberg repo - apache/iceberg#8171
Now shall I close this one?

[nastra]

thanks @mhmohona, yes this one here can be closed and I'll review #8171