[SEDONA-680] Remove rasterio from mandatory dependencies

[jiayuasu]

Did you read the Contributor Guide?

• Yes, I have read the Contributor Rules and Contributor Development Guide

Is this PR related to a JIRA ticket?

• Yes, the URL of the associated JIRA ticket is https://issues.apache.org/jira/browse/SEDONA-680. The PR name follows the format [SEDONA-680] my subject.

What changes were proposed in this PR?

This is to address several issues reported by users: #1688 #1574 #1607

1. Move rasterio dependency to optional dependencies
2. Add explanation in doc

How was this patch tested?

Passed local test

Did this PR include necessary documentation updates?

• Yes, I have updated the documentation.

[Kontinuation]

Simply changing the dependency to optional may not be sufficient. sedona.sql.types imports raster_serde, which imports rasterio transitively.

I'll append new commits to this patch and run additional tests without rasterio installed on GitHub Actions.

[jiayuasu]

@Kontinuation Agree. Forgot that part. We need to bypass that part too. Please go ahead and append commits.

[Kontinuation]

@Kontinuation Agree. Forgot that part. We need to bypass that part too. Please go ahead and append commits.

Now it is working.