Docs : add s3 access-point documentation

[singhpk234]

Adds documentation for using s3 access-points :

• Introduced in AWS: Add support for s3 access points #4334

slack thread : https://apache-iceberg.slack.com/archives/C025PH0G1D4/p1645066803099319

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cc @rdblue, @jackye1995, @rajarshisarkar, @anuragmantri

[anuragmantri]

Looks good to me. Thanks for making the change.

@jackye1995 - Are we still adding docs changes to the main Iceberg repo? I remember a discussion in dev list on moving this out.

[flyrain]

Thanks @singhpk234 for working on this. It is really helpful. Wondering if we can elaborate more on how multi-region access is enabled by this feature. I assume we just need to clarify that one access point can access multiple buckets cross-regions. For the below example, we can add a spark-sql config with the different bucket name and the same access point, so that user can understand better how it works.

[singhpk234]

I assume we just need to clarify that one access point can access multiple buckets cross-regions. For the below example, we can add a spark-sql config with the different bucket name and the same access point, so that user can understand better how it works.

Makes sense, have made the changes, Thanks @flyrain :) !!!

[jackye1995]

thanks for the work!