add elevation and slope properties

[sebastienlanglois]

Pull Request Checklist:

• This PR addresses an already opened issue (for bug fixes / features)

• (If applicable) Documentation has been added / updated (for bug fixes / features).

• (If applicable) Tests have been added.

• CHANGELOG.rst has been updated (with summary of main changes).

  • Link to issue (:issue:number) and pull request (:pull:number) has been added.

What kind of change does this PR introduce?

• This PR adds functions in the GIS module to extract elevation, slope and aspect ratio from a set of basins.
• This also fixes a small bug (of lack of feature) in the current GIS module that limited the land use classification to the bounding box of a watershed rather than its boundaries.

Does this PR introduce a breaking change?

No

Other information:

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[RondeauG]

LGTM!

[sebastienlanglois]

Tests are failing maybe because of Planetary Computer's breaking changes on June 6th. It's probably a quick fix if someone needs this PR quickly or else, I will be back at work in 2 weeks to fix it before merging.

[Zeitsperre]

@sebastienlanglois

They changed a URL and our security hardening failed the builds as a result. I'll go about unblocking them.