Remove use of fiona

[peanutfun]

Changes proposed in this PR:

• Remove explicit use of fiona package

This PR fixes #

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[peanutfun]

@emanuel-schmid Why do we want to remove the use of Fiona at all? In the tests, I have the issue that pyogrio (the GeoPandas fallback for fiona) seems to be less compatible with the data. Especially reloading the shape files with the cartopy shapereader (which uses pyshp if fiona is not installed) seems to be troublesome. Maybe we should just add fiona to the dependencies?

[emanuel-schmid]

The plan is not to remove the use of fiona, altogether but the explicit dependency. I was hoping that we can leave it to GeoPandas to establish a proper environment. In the past there have been hick-ups with the order of import executions, so there seem to be conflicts.
In any case, i consider fiona as low level, and if there is no good reason to be explicit about low level packages we should restrict ourselves to high level ones.
However if there is good reason, as you say, we should perhaps write some tests instead. (;

[peanutfun]

@emanuel-schmid With geopandas v1.0, I had to add fiona explicitly to the dependencies to make the tests pass (even though I removed all explicit use of fiona in the code)

[peanutfun]

@emanuel-schmid How do we continue? I think it's a bit confusing that we remove all explicit uses of fiona and then add it as dependency 😅 I suggest we do not change the code but simply add fiona as dependency. Then we can upgrade to geopandas v1.

[peanutfun]

We decided to add fiona as explicit dependency instead. Closing.