Add modelsearch - A library for indexing Django models

[rxm7706]

A library for indexing Django models with Elasicsearch, OpenSearch or database and searching them with the Django ORM

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[rxm7706]

Dependency for conda-forge/wagtail-feedstock#83

[github-actions]

Hi! This is the staged-recipes linter and your PR looks excellent! 🚀

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipes/modelsearch/recipe.yaml) and found it was in an excellent condition.

[rxm7706]

@conda-forge/help-python, ready for review!

[traversaro]

CI is failing.