Add tall building areas, fixes to building areas and main

[einoyrjanainen]

Description

Adds a new tall-building-areas algorithm that filters buildings by height class before delegating to the existing building areas workflow.

Also fixes GeneralizeBuildingAreas so it does not require building_function_id unless filtering is actually enabled, which avoids the KeyError when running the tall-building workflow with datasets that do not have that column.

Type of change

• Bug fix

• New feature

• Other

• Non-breaking change

• Breaking change

Developer checklist

• A CHANGELOG entry has been included (only when change is visible to users)

[JuhoErvasti]

I'll leave a general comment; the code itself for the most part is OK, but IMO this does not need to be its own algorithm, since the only thing that's different is that some features are filtered out. I see these options:

a) we leave the filtering up to the downstream user(s)
b) we add the filter step to GeneralizeBuildingAreas
c) we add GeneralizeTallBuildingAreas but make it inherit GeneralizeBuildingAreas, which would let users control its parameters