Need to be able to set a user-agent for overpass-api.de

[arminus]

As of ~ April 18, overpass-api.de requires a user-agent to be set on each request, see drolbr/Overpass-API#791 (comment)

Presently, this doesn't seem to be supported by the overpy wrapper.

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[alnzrv]

This PR fixes the issue but it's still open since 2024: #123

[gedankenstuecke]

This PR fixes the issue but it's still open since 2024: #123

As I wanted needed those changes for a project, I made a version that includes those changes and applies them on the latest main branch of this repo: https://codeberg.org/gedankenstuecke/python-overpy