Add Codecov (or similar tool) to workflow to check coverage for fork PR's

### Description

See details in #234 why we need a different tool than SonarCloud for forks (TLDR: fork PRs do not have access to secrets).

Codecov is a tool that does not require any secrets for public repos, and is also free for open source projects. https://github.com/marketplace/actions/codecov

It may be valuable to add this to our workflow to ensure fork PRs also fulfill our internal test coverage requirements.

### Additional Information

_No response_

### Tasks

_No response_

### Acceptance Criterias

_No response_

Start by reading issue #234 and the repository's existing workflow that uses SonarCloud. Evaluate the Codecov GitHub Marketplace action or a similar tool for public fork pull requests, then verify that coverage is checked without repository secrets and still meets the internal coverage requirement.

Written by the indexing model from the issue text.