Add ConcaveHull from geos lib

[valri11]

Description

Add ConcaveHull from geos lib

[peterstace]

Hi @valri11, I attempted to run the CI jobs against your branch, but some of the tests are failing. I'm still not sure why CI is not running for your branch, but you should be able to reproduce the issues locally. The failing commands are:

make lint
make goes

The make lint errors look pretty trivial to fix.

The make geos errors might be a bit harder. They're failing because GEOSConcaveHull_r was only added in GEOS 3.11, which prevents the github.com/peterstace/simplefeatures/geos package compiling against earlier versions. You may be able to solve this by using the same approach as GEOSMakeValid_r and GEOSCoverageUnion_r, which were only introduced in GEOS 3.8.

[peterstace]

@valri11 , I've altered the github actions config in https://github.com/peterstace/simplefeatures/pull/601, which should hopefully resolve the issue where actions are not running against your fork. For actions to run, I think you'll need to:

• Push another commit to trigger it.
• Then I'll need to (once-off) approve your fork (as per https://docs.github.com/en/actions/managing-workflow-runs/approving-workflow-runs-from-public-forks).