Add load_stac to localprocessing

[clausmichele]

Added a copy paste version of load_stac into the LocalConnection object.
This will allow me to use it in this way:

import openeo
from openeo.local import LocalConnection
local_conn = LocalConnection('')
url = "https://planetarycomputer.microsoft.com/api/stac/v1/collections/landsat-c2-l2"
spatial_extent = {"west": 11.259613, "east": 11.406212, "south": 46.461019, "north": 46.522237}
temporal_extent = ["2022-06-01","2022-06-15"]
bands = ["red"]
properties = {"eo:cloud_cover": dict(lt=50)}
s2_cube = local_conn.load_stac(url=url,
                    spatial_extent=spatial_extent,
                    temporal_extent=temporal_extent,
                    bands=bands,
                    properties=properties)
s2_cube.execute()

@soxofaan we would need to understand if we could reuse the code I'm developing here Open-EO/openeo-processes-dask#127 to get the cube metadata, since from the url only is not so easy, especially for big STAC Collections.
If the metadata is not set correctly, the client unfortunately doesn't allow to proceed in many cases. By the way, is it possible to deactivate manually the checks on the metadata?

[soxofaan]

we would need to understand if we could reuse the code I'm developing here Open-EO/openeo-processes-dask#127 to get the cube metadata

The local processing feature currently depends on openeo_processes_dask[implementations], so it should be possible to reuse functionality from there.

By the way, is it possible to deactivate manually the checks on the metadata?

yes, I'm considering something like that under #442

[clausmichele]

@soxofaan I added the code that, once the load_stac PR in openeo-processes-dask will be merged, will load the metadata using that implementation. It adds some overhead in terms of time, but in the meanwhile validates also the load_stac call.

[clausmichele]

@soxofaan the changes that we discussed about have been implemented, you could now review and merge!

[soxofaan]

some minor stuff

[clausmichele]

@soxofaan points from review addressed!

[soxofaan]

merged in 8d1d947