Link from datatable to related scenario bundle

[jh-RLI]

Summary of the discussion

This PR reorganises some core functionalities of the factsheet app. For the time being, some duplicated functions are also introduced, which can be removed from views.py later. The structure of the oekg connection is separated from views.py and a new module called oekg is introduced.

The oekg module also contains a filters.py module that implements the relevant functions to obtain the corresponding scenarios for each table. In this way, we can retrieve all scenarios for each table listed as either an input or output dataset.

Type of change (CHANGELOG.md)

Added

Add "Related Scenarios" tab to the data table details page: New functionality to retrieve all scenarios (from scenario bundles) where the current table is list as input or output dataset #1588

Workflow checklist

Automation

Part of #1305

PR-Assignee

• [x] 🐙 Follow the workflow in CONTRIBUTING.md
• [x] 📝 Update the CHANGELOG.md
• [ ] 📙 Update the documentation on mkdocs

Reviewer

• [ ] 🐙 Follow the Reviewer Guidelines
• [ ] 🐙 Provided feedback and show sufficient appreciation for the work done

[jh-RLI]

Basic but working implementation: